1Fifty years ago, France witnessed the birth of historical demography, which in a short space of time produced a massive harvest of knowledge on the populations of the seventeenth and eighteenth centuries and rejuvenated whole areas of social history. Setting out to understand the mechanisms of the post-war recovery in fertility, Louis Henry was able, within a few years, to forge an instrument of great scientific value whose components—concepts, sources, and methods—were not, however, entirely new.
2Drawing on an abundant literature but also on the rich material in the Louis Henry and Pierre Depoid papers, Paul-André Rosental retraces Henry’s intellectual journey. He shows how the intrinsic qualities of the demographer’s model combined with the specific conditions of the period to ensure the model’s overwhelming success among historians but also among population specialists around the world. Historians saw the new discipline as an exemplar of scientific and quantitative history, fully consistent with the principles of the École des Annales. For demographers, it contributed fundamental theoretical concepts, particularly in the area of fertility; at the same time, it fuelled the ongoing debate over population policies for the developing countries, where fertility behaviour and its changes played a decisive role.
3By demonstrating the links between the internal logic of Louis Henry’s work and the scientific, institutional, and political contexts, P.A. Rosental sheds new light on the rise of a discipline whose relative decline today remains perhaps to be explained.
“You may, no doubt, ﬁnd it odd that to answer the two questions forming the core of our subject — ‘Where are we?’ and ‘Where are we headed?’ — we begin by answering a third: ‘Where were we yesterday and the day before?’. This reference to the past is, however, essential, for it alone can tell us about the day after.”
5In the decades that followed World War II, historical demography was a ﬂagship discipline in the social sciences. It was one of the most “cumulative” specialities ever to emerge in the historical sciences. Its at times revolutionary results, combined with its capacity to embody “scientiﬁc” history and its ability to scrutinize the anonymous masses dear to the pioneers of the École des Annales, made it a symbol of the New History. In the early 1970s, it won acceptance among cultural historians and historical anthropologists and began to be practised around the world .
6The history of the discipline is inseparable from that of its founder, Louis Henry. In a previous article, we studied the reasons for his success in the historians’ community (Rosental, 1997). The issue we address today is logically antecedent: why did Henry invent historical demography? We can investigate it from two angles. First, how did a demographer become interested in the population history of pre-industrial Europe, and attract his peers’ attention to his ﬁndings? And second, why was he successful when countless earlier projects on the history of population had failed to capture simultaneously the interest of historians and population statisticians?
7By offering a conceptual framework, a source (parish registers), research instruments (family reconstitution forms), a method, a period of predilection (the seventeenth and eighteenth centuries), and a unit of analysis (the parish), Louis Henry was undeniably an inventor and a founder. Yet none of the components of his model was, strictly speaking, an innovation. Population history is a very old genre. Rich and diverse (Dupâquier, 1984; Mols, 1954), it began to be institutionalized between the two world wars, with the founding of a Commission for Historical Demography in 1928 under the auspices of the International Congresses of Historical Sciences (Bulletin du Comité international des sciences historiques 2, 1929, no. 6; Daszynska Golinska, 1930). It had been practised throughout Europe since at least the nineteenth century by local history enthusiasts who compiled family and village monographs touching on many issues of interest to demography (Goubert, 1956). Not only did Louis Henry not “invent” the administrative unit of observation (the parish), the time unit of observation (the long period), or the source (parish registers), he did not even “invent” the instrument that became the hallmark of his method: the family reconstitution form (ﬁche de famille). Here and there, some amateur historians had ventured beyond the simple tabulation of records to centralize the information collected on the demographic events in the life of households or even lineages (Levron, 1959).
8Certainly, demographic rigour is one of the characteristics of the Henry method and one of the keys to its success, and yet it too had a precedent. In 1942, the Swedish demographer Hannes Hyrenius — who, like Henry, was interested in the microscopic analysis of marital fertility — went down the path that the Frenchman was to take ten years later in using nominative registers from past periods. But his work made no real impact. Published during the war, it dealt with Baltic parishes and was written in Swedish. Most crucially, at that time, neither the institutional setting nor the demographic conceptual framework made it genuinely relevant in the eyes of specialists .
9By contrast, in the mid-1950s, specialists regarded Louis Henry’s ﬁndings on pre-industrial European populations as fundamental to their theoretical debates and their expertise in population policy. While the intrinsic power of Louis Henry’s model — i.e. its coherence and its capacity to be applied in diverse situations — was a prerequisite for its success, on its own it would not have been enough. To understand the dissemination of the Henry model, we must reconstruct the context that made it relevant to demographers but also to policy-makers around the world.
10In this respect, the history of historical demography offers a textbook example. The past two decades have seen a growth in the number of studies on the history of demographic thought, population policies, and the institutions in charge of implementing them. The task remains to analyse the relationships between these three spheres and the way in which they constructed themselves simultaneously (Szreter, 1993; Szreter, 1996). The Henry case is particularly interesting since it is, on the face of it, an unpropitious terrain for this demonstration. How can the history of past populations be thought to have such relevance for both theoretical demography and for the discipline’s practical applications? The example of Henry also enables us to understand why, in the 1950s, the population sciences increasingly identiﬁed themselves with demography, while they had been giving pride of place to economics, biology, and statistics in the interwar years.
I – The baby boom, a costly enigma
1 – A scientific and political issue
11When Louis Henry joined INED in October 1946, just one year after the founding of the Institute, his career had been far removed from historical preoccupations. Born in 1911, educated in military schools, Henry had been admitted to the École Polytechnique in 1931. Like many students of the 1930s classes (Guigueno, 1994), he graduated with ofﬁcer rank. Commissioned in the artillery, he was a prisoner for the duration of the war. After a brief stint back in the army, he was hired by INED while having no expertise in demography — let alone history — through the good ofﬁces of his fellow alumni of Polytechnique, Jean Bourgeois  and, most of all, Paul Vincent. Although they were his contemporaries, Bourgeois and Vincent had already some experience in demographic research, acquired during the Occupation in the small unit dedicated to the discipline at the Fondation Carrel .
12When Vincent, and later Bourgeois began their research, the outlook in the profession was predicated — as it had been between the wars — on the dreaded downward trend in the birth rates of western nations. Although Henry acquired the same theoretical references as his two ex-classmates , his thinking was rooted in a totally different context: that of the mysterious upturn in the birth rate, as revealed by none other than Bourgeois himself. At the outset, everyone regarded it as a transient phenomenon, comparable to the one that characterized the two years that followed World War I. But after the high birth ﬁgures of 1946 and 1947, which received wide press coverage, the trend persisted into 1948. Henry voiced his surprise in a series of lectures. With his friend Jean Bourgeois, but against the opinion of Alfred Sauvy , he came to the view that “fertility has risen very sharply from its pre-war level” and set out to ﬁnd the explanation.
13In the following years, this euphoria often gave way to uncertainty and hesitation. The year 1949 was again greeted with apprehension. Demographers feared that the 1919-20 scenario might yet repeat itself. The catch-up might simply have lasted longer this time, because couples had been separated longer. Again, the facts “disprove this more or less openly articulated expectation […]. Everyone, of whatever opinion, would like to know the causes of this inﬂux of newborn and to know whether it is likely to last” . Had the exhausted western world overcome its reluctance to procreate and chosen life again? The question of whether fertility had actually increased became a subject of polemics for years. The difﬁculty of providing a clear-cut answer is not hard to imagine, given the exceptional conditions that had characterized the war and its aftermath.
The Fonds Louis Henry [The Louis Henry papers]
14Louis Henry was directly exposed to this unprecedented demographic suspense. In June 1948, he was assigned to the computation of “family projections” — a subject he was never to abandon and that would lead him to population history. At the same time, Alfred Sauvy gave him responsibility, alternating with his friend Bourgeois, for “La situation démographique”, a quarterly summary description of the French demographic situation published in the journal Population . Henry thus monitored — practically as it was occurring — the unpredictable course of the birth curve, in particular by means of a convenient indicator, the number of “pregnancy cards” issued in Paris.
15Louis Henry’s intense preoccupation with the issue was due to the modus operandi of INED, whose remit was to provide hard demographic intelligence, especially to the government (Rosental, 2003). Sauvy and his inﬂuential Technical Committee (the equivalent of today’s Scientiﬁc Council) explicitly gave precedence to “applied” over “basic” research . Thus for Henry the theoretical issue was simultaneously a public policy issue. The reality of the baby boom would determine the appropriateness of massive investment in public or private infrastructure, most notably schools and housing. Admittedly, the link was less mechanical than might be assumed. The evidence of a sustained increase in fertility justiﬁed capital investments, which Louis Henry advocated. But at the same time, Henry shared the fear of a “Malthusian reaction” — be it the alarm in English-speaking countries about population growth in the developing world, or the opposition in French “conservative circles” to the expenditures that population growth would induce. These fears were expressed repeatedly, most notably by INED’s director, Alfred Sauvy, but also by his research staff . In this case, professional expertise was inseparable from pronatalism, a position publicly advocated in the Institute’s name . Henry supported and participated in this “anti-Malthusian” struggle. Through lectures, newspaper articles, rejoinders to journalists, and memoranda to senior civil servants (Fonds Henry, art. 8), he sought to minimize the link between the demographic surge and the spending on infrastructure.
16In regard to family allowances, the issue took a paradoxical turn. The system — developed in the 1930s and later under Vichy, and greatly extended after the Liberation — was the standard bearer of French “voluntaristic” demographic policy. But INED researchers feared that it contained the seed of its own destruction. Designed for a context of depressed birth rate, it would become a source of runaway spending if the birth rate recovered. This was a cruel dilemma: a system threatened by its own efﬁciency. The uncertainty about the population trend was thus compounded by uncertainty about its ﬁnancial implications and, most of all, its political fallout.
2 – From forecasting to history
17In this context, forecasting took on a strategic dimension. Both the “erratic ﬂuctuations of the gross and net reproduction rates in the past ten years” (Clark, 1949) and the advent of new analytical tools fragmented the perception of the demographic situation and caused demographers to lose their bearings. The immediate postwar years represented a complete reversal in comparison with the early days of demographic forecasting. Since the 1920s, population experts tended to emphasize the predictability of phenomena and would extrapolate current trends into the future (Hajnal, 1947b). In France, pioneer Alfred Sauvy actually feared the perverse effect of the momentum of population phenomena: why would political rulers ﬁnance population policies whose effects would be felt only in the very long run (Sauvy, 1928, 1929 and 1932)?
18The uncertainty surrounding the unexpected baby boom shook this conﬁdence. In the United States and in Britain, well-funded studies during the war were premised on the unquestioned assumption that the depressive trend of the 1930s would persist (Notestein, 1944). Barely had their ﬁrst ﬁndings become known that the evidence of an upswing in the birth rate became undeniable. This shock (Henry, 1966) was accompanied by a loss of innocence, with many demographers now recognizing that research sponsors were more interested in obtaining scientiﬁc legitimacy for their projects than guidance for enlightened policy-making (Cox, 1954). The harshest self-criticism came from the British demographer John Hajnal. After attacking the concept of demographic forecasting at the 1954 World Population Conference in Rome, he questioned the very usefulness of the profession. How could its existence be justiﬁed if the sophisticated techniques for the analytical decomposition of demographic phenomena performed no better, in the area of forecasting, than the rudimentary tools of the interwar years (Benjamin et al., 1955; Henry, 1966)? Demographers’ predictions, Hajnal argued, had no scientiﬁc value. At most, by providing a basis for population policies, they could have self-fulﬁlling effects.
19In the mid-1950s, Louis Henry corresponded with Hajnal. In a letter of 29 December 1955, he explicitly defended demographic science as an indispensable guide for action. Yet he too had drawn lessons from the surprise of the baby boom and the instability of the previous two decades. Henry was simply more “constructive” than his interlocutor in his cautious acceptance of forecasts that extrapolated current trends to the very short term . He based them not on theory but on “empiricism”, in one of the very rare writings in which he refers explicitly to his experience as artillery ofﬁcer.
20Hajnal countered with a totally sceptical view . Yet, beyond their disagreement, the main point was that for both men, the fallibility of forecasting enhanced the value of understanding past phenomena, the main difﬁculty being in demonstrating their importance to paymasters misled by an erroneous concept of “effectiveness” . Hajnal (1955) stated publicly that one of the few good ways in which one could claim to talk about the future was by studying the past. Likewise, the reference to the past formed the leitmotiv of Louis Henry’s many public lectures to non-specialists on the French demographic situation . This response to an audience eager for forecasts was the ﬁrst source of Henry’s interest in the demography of times past.
3 – Introducing nuptiality
21In the interwar years, most authors discussed each country’s fertility as a whole. Demographers had concentrated their attention on overcoming the bias linked to the age distribution or, as Alfred Lotka, on integrating fertility in a general dynamic theory of population. Few had thought to distinguish “marital” fertility from “illegitimate” fertility, and in any case, only a tiny minority of births in western countries occurred out of wedlock. The methods they had proposed took on an entirely new relevance at the end of World War II .
22In a widely discussed article, Hajnal (1947b) showed that in several countries the upturn in birth rates coincided with an increase in the number of marriages. This trend mechanically increased the proportion of young couples in the overall married population. Now, in these populations practising contraception, births tended to occur in the early years of marriage. Hajnal concluded that demographers were in danger of confusing two different interpretations of the fertility recovery. The ﬁrst concerned the behaviour of spouses. Couples, it was argued, now wanted a greater total number of children. Owing to the inertia of preferences, the upswing might persist. A second explanation, in contrast, minimized the impact of the phenomenon. In this view, earlier marriage had merely led to a change in the timing of births and caused a temporary rise in the period indices .
23Nuptiality thus became an essential element of the postwar demographic scene. This innovation was at the same time regarded as a means of taking into account the male population, whose exclusion from the analysis continued to fuel controversy among demographers . Similarly, the introduction of a cohort approach conferred a new analytical status on the question of contraception. In the U.S., the links between differential social fertility and the use of contraception had been measured empirically in the 1930s, through a series of surveys funded by birth control advocates (Kiser, 1971). After the war, the normative ideology of birth control and the investigation of actual practices converged. Demographers emphasized the importance of couples’ planning their number of offspring (Hajnal, 1947b). The semantic shift in the 1940s from the stern “birth control” to the more euphemistic “family planning” illustrates this new perception, in a broader setting than the scientiﬁc community alone (Hartmann, 1997).
24The distinction between populations that were assumed to widely practice contraception, and the other populations, emerged from this phase in a new form. At the time, a strict analytical division separated these two types of population: those in which couples decided on the size of their family in advance, and those in which fertility was not deliberately controlled . We will encounter this dichotomy throughout this article. In the post-war years, demographers believed that contracepting populations had clear objectives, and that timing was the only uncertain factor (Hajnal, 1947b). The speed with which couples reached their fertility targets depended, in particular, on economic conditions . The fertility of populations assumed not to be practising contraception was governed by laws of its own. In a period when concern for regulating population growth in the poor regions of the planet was taking shape, demographic theory legitimated a division between the study of fertility in the industrialized countries and in the developing countries .
4 – Family micro-history and demographic macro-changes
25The emphasis on marital fertility and the opposition between contracepting and noncontracepting populations structured the model of historical demography developed by Louis Henry a few years later. But its very purpose — the microscopic analysis of the reproductive behaviour of couples — also originated in the theoretical debates about the baby boom.
26In his 1947 article, one of Hajnal’s targets was the interpretation of the spectacular recovery of German fertility during the early years of Nazism. The political importance of the subject revealed the limits of the “macroscopic” indicators used by the demographers of the interwar years. Adopting a rationalist stance, Hajnal regarded aggregate demographic data and the fertility or reproduction rates that could be derived from them as too imprecise. Their use left too great a margin for personal interpretation and hence for ideology. The British demographer preferred a “microscopic” approach that focused directly on the behaviour of couples. Did German fertility change in 1933 and, if so, was this outcome speciﬁc to Nazism? An answer to this question would require determining whether, for an equivalent duration of marriage, German couples of the mid-1930s had more children than those of earlier cohorts or of other countries. The lack of sufﬁciently detailed data caused the sceptic Hajnal to suspend judgment.
27His reasoning exempliﬁes the issues and methods that spread after the war (Clark, 1949). Was the upswing registered by fertility indices the result of statistical bias or of a revolution in personal behaviour? The growing use of opinion polls and the introduction of sampling techniques in survey procedures made such investigations possible (Hyrenius, 1948; Shryock, 1950). But because of their cost they were not within everyone’s reach, and many demographers around the world had to continue to rely on national statistical sources.
II – Family statistics and their limits
28In the interwar period, the crucial variable for computing fertility rates was the woman’s age at childbirth. The new approaches took a growing interest in family formation , and particularly in the duration of marriage of the couple (Hajnal, 1947b). Except for a privileged few with the resources needed to conduct ad hoc surveys , the only solution was — as in the prewar years — to use the statistical yearbooks published by the national and international institutes. For France, Louis Henry had to rely on the so-called “family statistics”. Drawn from the ﬁve-year population censuses, these data concerned the demographic structure of households. Depending on the information requested by the census schedules, the “family statistics” showed the number of surviving children or even the total number of children ever born, their ages (on a continuous scale or by age group), and those of the spouses. This information often required special processing by the Statistique Générale de la France (SGF), particularly for matching family characteristics (number of children, and optionally the age structure) with the age or occupation of the spouses. The cost of gathering and processing these data was high, and their production required the consent of the Finance Ministry. Yet the family statistics were not intended only to satisfy scientiﬁc curiosity. They appear to have been compiled for the ﬁrst time in 1886, in response to concerns over the level of the French birth rate (Landry, 1945, p. 160). In the early decades of the twentieth century, their production was also linked to eugenic considerations: measuring the fertility of the different social groups addressed worries that the “gifted” social classes were reproducing more slowly than the “dysgenic” ones .
29More prosaically, the most powerful determinants were immediate questions relating to social policy. From the 1920s onward, the expansion of the family allowance system — organized by economic sector and occupational status — gave new importance to the issue of the fertility of social groups. The Finance Ministry was interested less in fertility than in the number of dependent children. This concern made the breakdown by age unusable for demographic applications. Louis Henry continued to be handicapped by this after the war . Another problem seems to have been, at least between the wars, an endemic under-reporting of the number of children (Henry, 1953d).
30After World War II, neither the founding of INED nor the expansion of the SGF (now the National Institute for Statistics and Economic Studies: INSEE) overcame all the obstacles of previous decades . One of the sources of INED’s grievance against INSEE was the difﬁculty the former had in inﬂuencing the choice of information requested on census schedules and in obtaining surveys on speciﬁc topics (Rosental, 2003). The problem also arose in other countries and in international organizations. Cost constraints, or even the requirement that publications be easily understandable, generated a structural tension between the logic of statistical institutes and the needs of demographers — needs increased by the new sophistication of the tools of their discipline.
31Louis Henry’s intellectual journey toward population history cannot be understood without reference to this frustrating shortage of data . He began by trying to make do with French family statistics. While making imaginative use of the fertility data drawn from the records of the family allowance system (Henry, 1953d), and meeting with refusals from INSEE via Alfred Sauvy, Henry began a virtual world tour through the statistical yearbooks. It was in the Czechoslovak yearbooks that he found the only available data on legitimate births by parity and birth intervals (Henry, 1951). From the Norwegian statistics, he used the distribution of legitimate live births by parity . In the early 1950s, whereas he had never travelled outside of Europe yet, Henry found study materials in Australian and even Japanese statistical yearbooks (Henry, 1953b, 1954a and 1954b); and on many occasions he sought to put pressure on data producers .
32It is possible that these investigations led Louis Henry to internalize an approach that would strengthen his interest in historical demography: the integration of space and time into a continuum that allowed comparisons of all kinds (see below). The fact remains that these comparative solutions were at the time second-best solutions. They were suitable for working only on a speciﬁc aspect of fertility, but not on the concept as a whole. And in fact, Henry had begun to elaborate his own approach by focusing, in particular, on the “parity progression ratio”.
33The method, which sought to “reduce the post-war disturbances as much as possible”, captured the importance of birth order in family formation. It provided a convenient index of fertility change. By the early 1950s, Louis Henry was able to identify with precision the differences in behaviour compared with couples in the 1930s. Like some demographers in other countries, he deduced that the revival of French fertility would last . While the parity progression ratios thus contributed to the international debate on the reality of the baby boom, they also served the practical purpose of better anticipating the cost of the family allowances that would be paid to couples (as in the interwar period, the allowances were not proportional to the number of children). But the basic fact was that the method was chieﬂy designed to circumvent the limitations of the statistical sources of the time. To take his analysis of fertility a stage further, Louis Henry decided to plunge into the population history of modern Europe.
III – A necessary benchmarking
34Parity progression ratios are a convenient but relative indicator. They allow comparisons between nations or periods, but not absolute assessment of reproductive behaviour. The need for a benchmark is obvious but raises two problems. The ﬁrst is of a theoretical nature: what “pure” situation should be chosen as the standard? Henry responded by introducing the concept of “natural fertility”, which is held to denote the reproductive capacity of non-contracepting couples. The second difﬁculty is of an empirical nature: how does one measure “natural fertility”? As a rule, there is little statistical information on populations of developing regions, who are assumed to be non-contracepting. It is tempting to look to populations of the past — those that predate the “demographic transition”. Around 1945, however, it was assumed that the behaviour of that “pre-statistical” era could not ever be measured. Louis Henry’s contribution was to surmount this theoretical and archival barrier and, by the same occasion, to promote history as a tool of demographic analysis.
1 – The impossibility of measuring natural fertility
35For Henry, the “pure” components of fertility are ﬁrst and foremost physiological, such as the female propensity to conceive during a menstrual cycle. But other components are social or cultural, starting with breast-feeding practices. Subject to extreme individual variations, they determine the pace of the mothers’ return to a new fecund state. This set of factors goes by the name of natural fertility . The expression is misleading, as the notion is both related to biology and conditioned by culture .
36Among the factors that Henry labelled as “ physiological”, natural fertility includes the proportion of sterile couples (which varies with age), the length of the infecund period in fertile couples and, most important, “fecundability”. Deﬁned as the probability of conceiving during one menstrual cycle (Henry, 1951 and 1952), this concept was developed by the inﬂuential statistician and economist of Fascist Italy, Corrado Gini, with whom Henry corresponded after the war . Henry also cited—not uncritically — the eminent American biologist Raymond Pearl (Henry, 1953a) . By his references to these two authors, complemented by his study of physiology textbooks , Henry positioned himself, in the postwar years, in the line of the demographic tradition that is closest to the natural sciences. Indeed, his biologism was sometimes attacked, as Gini’s had been before him (Grauman, 1959). Although not a fervent eugenist, Henry did not hesitate to borrow from this current of scientiﬁc thought — which had ﬂourished between the wars — the notions and tools that seemed useful to his research, ignoring or masking their ideological implications. His “pragmatism” toward Gini, whose scientiﬁc positions were challenged in the postwar world, is in this respect revealing of a more general attitude .
37At the same time, other determinants of natural fertility were sociocultural or, if one prefers, anthropological, such as breast-feeding practices or “customs and taboos” inﬂuencing the resumption of intercourse after delivery. If we wanted to subject Henry’s ideas to retrospective and somewhat anachronistic criticism, we would have to emphasize his ultraculturalist view of behaviour at least as much as his biologism .
38The notion of natural fertility applies, in the ﬁrst place, to “non-Malthusian” populations — the term still used in the immediate postwar years to describe non-contracepting populations. But it also applies to “Malthusian” populations, within the conﬁnes of a fairly rigid vision typical of the period. Since the couple decides at the outset how many children it wants, it will start with a natural fertility phase, and will then cease to reproduce once it has reached its desired family size. In this second phase, given the less than total effectiveness of its contraception, the couple may conceive unwanted children. At the aggregate level, their distribution in time will bear some resemblance to that of couples who follow the “natural fertility” model. Lastly, the reference to natural fertility allows an estimation of phenomena such as the proportion of prenuptial conceptions.
39By overcoming the great post-war analytical divide between contracepting and non-contracepting populations , the concept of natural fertility was suitable, in Henry’s view, as a universal benchmark. From his earliest work — on colonial populations — Henry made empirical use of the notion of a space-time continuum. Always using the most robust statistical series, he looked in other temporal or spatial contexts for populations with characteristics comparable to those of the populations he was studying, on which more data existed. For example, by identifying for Spain in 1880 and for Italy in 1900 two male-mortality curves that enclosed the curve for Algeria in 1936 between them through the adult ages, he used them to “adjust” Algerian mortality at older ages (Henry, 1947). In effect, Henry treated history as a stock of observations comparable with the colonial and developing-region populations . This approach, whose foundations were not made explicit, suffered from the limited number of statistical studies on historical populations that could be regarded as reliable 
40It is important to realize the powerful constraint represented by this lack of evidence. At the time, demographers and historians distinguished between “statistical” and “pre-statistical” populations, depending on census availability (Rosental, 1997). As regards fertility, the division was overdetermined by the difference between contracepting and non-contracepting populations. From the nineteenth century, population specialists were aware of the difﬁculty of studying the mass diffusion of contraception, which partly preceded the era of censuses. But this obstacle took on a new signiﬁcance in Henry’s generation. U.S. and British studies carried out in the 1930s had shown the effect of contraception on differential fertility by social class. The enigma of the baby boom underscored the importance of the intimate decisions of couples. For the postwar demographers, the opposition between contracepting and non-contracepting populations corresponded to a deep anthropological division, a “break between civilizations” (Chevalier, 1946).
41For pronatalist demographers, the relevance of the question was intensiﬁed by nostalgia for lost greatness. France’s inﬂuence, they argued, was waning because of the early decline in its fertility at the end of the eighteenth century, several decades before the rest of Europe. At a more personal level, the correspondence between Louis Henry and Jean Bourgeois-Pichat shows the two men’s sensitivity to the worried debates on contraception that were stirring the Church and Catholic circles at the time. Now, faced with the crucial question of dating the advent of contraception, demographers had difﬁculty extending knowledge of past populations back beyond the Napoleonic period (Bourgeois-Pichat, 1951; Vincent, 1947), and the historian Louis Chevalier had abandoned all hope for a ﬁrmly-based understanding of periods prior to the eighteenth century (Chevalier, 1946). Overcoming this time barrier was one of Louis Henry’s greatest achievements.
2 – A Northwest Passage in the archives
42The solution to the problem took shape in 1953. A few months earlier, Louis Henry’s attention had been drawn to a widely quoted article by Pierre Goubert (1952) that proposed a statistical analysis of the seventeenth-century parish registers of the Beauvaisis, a region north of Paris . These systematic registrations of population movements (baptisms, marriages, burials) had been the object of earlier but sporadic scrutiny by historians and local scholars. They had also been the focus of substantial critical evaluation by archivists, included in the curriculum of the École des Chartes, the French school for archivists and paleographers .
43It was through his critique of Goubert’s article that Louis Henry ﬁrst penetrated into the historians’ territory (Henry, 1953c). He designed a method of study that he would try out on three projects. To offset the lack of statistics for older periods, Henry initially relied on documents such as livres de raison (registers kept by heads of households) or genealogies. The opportunity to test these sources was given to him by Michel Fleury, deputy archivist of the département of the Seine, who told him about the data then being assembled on the patrician families of early modern Geneva . Meanwhile, Henry asked his assistant, Louis d’Adhemar, to assess the value of genealogical materials for historical demography. These have the advantage of being, so to speak, “pre-processed”: they provide instant information on the demographic event history of couples and lineages. On the downside, Henry was aware that this information cannot always be corroborated and is socially biased .
44The arrival at INED of a young Canadian trainee, Jacques Henripin , proved decisive. Henripin was analysing the genealogical data compiled in the previous century by Abbé Tanguay on the French Canadians in the seventeenth and eighteenth centuries (De Tanguay, 18711890; Henripin, 1954). The data were drawn from the old parish registers of Québec, so in helping Henripin, Louis Henry was able to judge for himself the richness of this source and the feasibility of exploiting it. Henripin was able to relate mother’s age at marriage and at the birth of her children, to study birth intervals, to analyse their sensitivity to infant mortality, and even to estimate “fecundability”. Using Henripin’s data, Henry refuted the hypothesis that birth spacing in non-contracepting populations was constant until sterility simply put an abrupt end to family formation. On the contrary, Henry noted that spacing remained constant only until the antepenultimate birth. It then increased slightly, and the interval between the last two births was much wider. The shortcomings of contemporary statistical publications were forgotten. For the ﬁrst time, Henry had identiﬁed a characteristic of “natural fertility”. He was to ﬁnd it again in very different contexts, and this strengthened his conﬁdence in the concept’s relevance (Henry, 1954a).
45Louis Henry’s interest in parish registers was reinforced by his encounter with Étienne Gautier. This “enthusiastic amateur, by occupation a civil servant in the Trade Ministry, had spent many holidays patiently reconstituting the families of his native village”  of Crulai in Normandy. Gautier brought Henry the results of his compilation of data from the pre-Revolutionary parish registers. Their availability and universality made the registers a precious source for investigating the demographic conditions in pre-industrial France. But they raised two series of problems.
46The ﬁrst was the problem of analysing the data source, and Henry began to tackle this in his 1953 article. He was helped by young historians whom INED hired for him on temporary contracts, and by Michel Fleury (1923-2002). It was with Fleury that Henry published in 1956 the manual that was to give historical demography its true deﬁnition, the monograph on Crulai being its ﬁrst full-scale application (Fleury and Henry, 1956; Gautier and Henry, 1958). Fleury also played a decisive role by putting Louis Henry in contact with the network of archivists interested in parish registers.
47A second, more serious obstacle was the time and energy required to extract data from the parish registers. For each geographic entity examined — in practice, a single parish, given the bulk of the data set — all the baptisms, marriages, and burials for the period of study had to be recorded on index cards; then for each married couple, a “family reconstitution form” (ﬁche de famille) had to be started . The implementation of the method was predicated on a division of labour in which the designer, Henry, would check and process the data gathered by countless collectors. Their training posed a problem , as did the project organization, even though that was probably one of Louis Henry’s strengths . But the greatest difﬁculty was to ﬁnd a large enough work force. Three main sources were used. First, local amateur historians who had compiled “unofﬁcial” population histories volunteered their services , as did secondary schoolteachers and members of the clergy teaching in Catholic schools. Second, one of the strengths of the Henry method was its accessibility to non-specialists: Louis Henry relied on non-historian volunteers identiﬁed by département archivists ; Alfred Sauvy and Michel Fleury did their best to get the heads of teacher-training schools (écoles normales) to channel their students toward the study of parish registers as a topic for their ﬁnal thesis. Third, Louis Henry actively sought help from the community of historians. His initiative was relayed by the Sub-Commission for Historical Demography, which reported to the French section of the International Committee for Historical Sciences . In 1954, Louis Henry publicized his method among historians through a series of lectures. Academic historians sympathetic to his call steered some of their students toward topics in historical demography .
48Teachers often delegated full responsibility for supervising these theses to Henry and his team . Not only did the demographer, assisted by Valmary, have a monopoly of the technical know-how, but the mechanical processing of the completed forms was taking place at INED. These academic pioneers of collaborative work with Henry effectively embraced a model of scientiﬁc and quantitative history that put into practice the injunctions of Ernest Labrousse and Fernand Braudel. More prosaically, in subsequent decades historical demography yielded an inexhaustible supply of topics for diplômes d’études supérieures and master’s theses (DH, 1980). By the late 1950s, however, voices were being raised among historians to denounce a method so time-consuming and repetitive that it deprived students of effective training in the discipline. The students themselves were not the last to be aware of these shortcomings .
49It is hard to gauge the extent to which these reactions drove Louis Henry to lead historical demography into a second, more ambitious phase. Between 1953 and the late 1950s, his main goal was to test a method and tools designed for data extraction , as well as to compile results from different geographical areas. But, in 1958, Henry changed the scale of his undertaking by presenting the project of a national survey in the journal Population. The aim was no longer to obtain results of general demographic value, but to reconstitute the population of ancien régime France by means of a purposeful and systematic survey. Seventeen years later, the survey provided the basis for a special issue of Population still regarded today as the basic reference on the demography of France in the modern period (Population, special issue, 1975; Dupâquier, 1988, p. 4; Brian, 1994, p. 9-24; Séguy, 2001). For Henry, history had become an objective in itself, and historical demography, which was overcoming the last pockets of resistance among historians , had established itself as a dominion of demography in historical territory .
IV – The uses of historical demography
50By choosing parish registers rather than already-constituted but less comprehensive sources such as genealogies and old enumerations, Henry experienced the same material constraints (length and cost of data extraction) as his colleagues performing contemporary surveys. Unlike them, however, he could not point to practical beneﬁts that were as visible and immediate. The question, therefore, is why Alfred Sauvy — beyond his undeniable personal interest in the discipline  — awarded Louis Henry the funds he needed. Nowadays, backing from a research institute for a survey would be commonplace. Before the Fifth Republic, however, the autonomy of INED was not protected by any ﬁrm ministerial commitment — any more than that of the other research agencies (Duclert, 1998; Picard, 1990; Ramunni, 1992). As with the other institutes, INED’s expenditures, and even its existence, were subjected to strict control by the Finance Ministry. This control extended to staff positions, as INED researchers were untenured contract workers. Under these constraints, Sauvy and his Technical Committee, whose favourable attitude toward applied research was noted earlier, sought to protect the Institute by integrating it into a state apparatus that was rapidly expanding with the growth of public policy. That a historically oriented project should have received backing in such a context deserves explanation.
1 – Natural fertility and reproductive biology
51The beginning of an answer lies in the uses of historical demography. Its implementation by Henry closely followed the development of the notion of natural fertility. This synchronism is, of course, anything but fortuitous. The demography of the past was regarded as an observatory whose ﬁndings could be applied immediately to decipher contemporary situations. The historical survey allowed a benchmarking of all the results obtained for the physiological determinants of fertility, and could therefore be used simultaneously for demographic and biological purposes.
52The study of the variation of sterility as a function of age provides an example. Louis Henry estimated it by combining conclusions based on “statistical” populations making little use of contraception (nineteenth-century England, rural Japan between the wars) and on “pre-statistical” non-contracepting populations (Geneva and Henripin’s French Canada). The convergence of results made it possible, in particular, to measure the age at which the rise in sterility accelerates . Henry also formulated proposals concerning the nature and extent of “adolescent sterility” . Likewise, he recognized early on that an increase in the last two birth intervals in the birth history of couples was characteristic of natural fertility. Through the accumulation of results, he was able to calculate the effect of infant mortality on the change in the length of the intervals (Henry, 1958).
53With time, the comparisons between non-contracepting populations, or between women in a given population, showed the importance of the variability of fertility in a “natural” regime. This dual variability increased the importance of breast-feeding, to which Henry was consistently attentive (Henry, 1952, 1957 and 1958). In all the cases examined, historical demography served as an adjunct science to biology. Henry’s ﬁndings were taken into consideration along with those concerning the Hutterites, a North American religious sect that did not use contraception. Although small and sociologically distinctive, it possessed “modern” statistical records. As Henry himself admitted, the consistency between the ﬁndings of Eaton and Mayer (1953) and their successors and those obtained by Henry enhanced the credibility of his results .
2 – Time and the other 
54Historical demography also had more indirect uses. Natural fertility was supposed to characterize non-contracepting populations in the developing world . After coming up against the gaps in statistics on the French colonies early in his career as demographer, Henry attributed the behaviour of preindustrial Europeans to the populations under French rule . The ambiguity of the concept of natural fertility was highlighted by these space-time comparisons: after a few years, Henry concluded that fertility levels were subject to continent-speciﬁc variations, a ﬁnding that reinforced his view on the “socio-cultural” underpinnings of natural fertility .
55For the time being, natural fertility made it possible to calibrate the results obtained in speciﬁc contexts, to situate populations with respect to one another, and to detect any implausible results that might be due to an idiosyncrasy of the data source . This became a privileged area of application for historical demography. Another application was in the area of methodology. Louis Henry transposed the experience acquired in his monographs to help demographers, and even colonial administrators, design their surveys in the French colonial empire or in developing countries . At one point, Henry even nurtured the ambition to make international organizations ﬁnance the development of historical demography . His recommendations were transmitted all the way to the UN Population Division . They focused, in particular, on sampling techniques and the checking of results. From this standpoint, it would be hard to overstate the contribution of historical demography and the “parish” approach to the changes then under way in the discipline. For a long time, demography and population science had worked at the level of aggregate populations, documented by national, regional or municipal statistics. The concept of the quantitative survey that focused in particular on recent advances in sampling methods (Blondiaux, 1998) and on the use of small samples, was ushering in a new methodological universe. Henry articulated the distinctive features of this type of “statistics of small numbers” by comparison with the classical techniques of demography .
V – How historical demography was received
56One of the keys to the success of historical demography — initially conceived as an indirect route for conceptualizing contemporary demography — lay in proving its operational worth. It is important to stress the transient nature of this conjunction. Some ﬁfteen years later, in the early 1970s, the presence of historical demography at INED would be excoriated by the ministry with supervisory authority over the Institute and — not without a measure of cultural populism — even by the press .
57For the time being, another factor that conferred legitimacy on the study of past populations was its acknowledged contribution to the fundamental demography of its time. The tangible embodiment of this was the family reconstitution form. The form’s headings — such as the column set aside for computing birth intervals — linked parish registers directly to the most topical issues of theoretical demography, which in turn were linked to population policies. The list of recipients of Henry’s book on old Genevan families (1956) shows that the survey on early modern Geneva was understood by all the leading demographers of the day as a major theoretical contribution. This list included notably David Glass of the London School of Economics, a central ﬁgure in the institutionalization of demography in the U.K. and, for the U.S., Christopher Tietze of the International and Functional Intelligence Section of the State Department in Washington, Frederick Osborn, Director of the Population Council in New York, and Frank Notestein, of the Ofﬁce of Population Research in Princeton . At the same time as historical demography was gaining acceptance in an international community that granted it a prominent role, it helped the young INED to conquer its scientiﬁc legitimacy and thereby improved its chances of survival. Although Sauvy and his Technical Committee had initially given precedence to “action”-oriented research, they quickly incorporated that criterion into the talking points designed to combat the recurrent threats from the Finance Ministry (Rosental, 2003).
58This recognition, in turn, was possible only because the international community of demographers was expanding rapidly in the 1950s — the real golden age of the discipline. In the U.S., the interwar years had seen the formation of a community of population specialists, a move encouraged by birth control activists and ﬁnanced by large U.S. foundations. The trend gained momentum with the creation of new foundations and the rise in the number of university chairs and study centres, the most inﬂuential being Princeton’s Ofﬁce of Population Research (OPR), set up before the war.
59The prime characteristic of postwar U.S. demography was its interpenetration with the main international organizations, the crossover being at once human, institutional, ﬁnancial, and political (Kiser, 1971; Szreter, 1993; Notestein, 1982). One of the key venues for interaction between U.S. demographers and top specialists from other countries — Jean Bourgeois-Pichat and Léon Tabah from France, John Hajnal from Britain, Hannes Hyrenius from Sweden — was the UN’s Population Division. The Division was in charge of the projects recommended by the Population Commission of the United Nations Economic and Social Council, which in turn was linked to the Department of Economic and Social Affairs. The function of the Division was to supply “facts and interpretations” to the U.N. bodies, specialized agencies, and member governments for their economic and social action programmes (Notestein, 1971; Revue de l’Institut international de statistique 1954, no. 1-3). During the 1950s, the Population Division effectively became one of the leading centres for the development of demography as a discipline.
60This was a radical transformation. Since the nineteenth century, scientiﬁc internationalism had been mediated by international congresses (Brian, 1989; Rasmussen, 1995). Their importance declined after World War II with the expansion of academic and research jobs and institutions. Initially, the international organizations played a major role in this new international reordering, by virtue of a belief in the reforming potential of the social sciences. Their conclusions, orchestrated by the international agencies, were expected to translate into large-scale programmes (Kiser, 1953; Lorimer, 1948; Notestein, 1971; Wittrock, Wagner and Wollmann, 1991).
61To this overall institutional framework we must add some short-term considerations. The UN Population Commission endorsed the opposition between “science” and “policy” and conﬁned itself to the purely scientiﬁc aspects of the discussion, even at the risk of losing inﬂuence . This was not an abstract preference, but the product of a diplomatic balance of power. Most U.S. demographers subscribed to the recent theory of the “demographic transition” . After a few years, the interpretation and use of that theory consisted in making family planning a tool of development, steering western donors toward demographic action rather than toward assistance or economic and social reform (Szreter, 1993, p.660-675; Hodgson, 1983; Notestein, 1982; Demeny, 1988; Greenhalgh, 1996; Kreager, forthcoming). This new incarnation of the Malthusianism and eugenics of the interwar years was increasingly supported by U.S. foundations (Hartmann, 1997; Greenhalgh, 1996; Donaldson, 1990).
62But the Soviet bloc attacked the policy’s “bourgeois” character and, by way of contrast, proclaimed its faith in population growth and in its own economic future (Benjamin et al.,1955; Hartmann, 1997) . Most importantly, it formed a common front on this issue with the Catholic countries (Bulletin international des sciences sociales 1954, no. 4). To avoid hardening this alliance, the U.S. government sacriﬁced its Malthusian convictions until the late 1950s (Szreter, 1993). This conﬁguration explains why — much to the chagrin of “Malthusian” demographers (Evang, 1954) — the Population Commission deprived itself of all effective power and, as is often the case, correspondingly overinvested the scientiﬁc ﬁeld.
63The reception of Louis Henry’s work was not, therefore, exclusively related to the evolution of demographic concepts. It was a consequence of an expanding international network, which attached central importance to fertility (Greenhalgh, 1996; van de Kaa, 1996) and to the production of novel empirical results . Both the baby boom in the West and the population growth in poor countries called for an understanding of fertility mechanisms. Their very conjunction posed a major theoretical problem, for even as the demographic transition “model” was spreading, it was being refuted by the upturn in the fertility of wealthy countries. The idea gained ground that the level of individuation in the industrialized countries was so high that demographers needed to delve into intimate decisions to analyse the ﬂuctuations in the birth rate . The transition from aggregate statistics to the micro-behaviour of couples opened a hidden continent to empirical investigation. Louis Henry’s analyses were part of a broader movement, in which the elementary demographic behaviour of couples was subjected to minute scrutiny. For a while, history served as a privileged observatory for demography.
64The success of historical demography was made possible by an institutional, political, and scientiﬁc conﬁguration speciﬁc to the 1950s. For some ﬁfteen years, the issues and methods suggested by Louis Henry established a direct link between history, demographic theory, and expertise in the service of population policy. The history of historical demography is, in this respect, representative of the history of demography in general. In the INED of the 1950s, the criterion of scientiﬁc success was to develop approaches that, while they embodied theoretical innovations, lent themselves also to practical applications. The condition for success was that these transfers between theory and expertise should be rapid and direct: the transfers involved concepts, results, and methods, but also teamwork organization methods, survey technology, and inquiry procedures. In France, Louis Henry was one of the researchers who best satisﬁed this dual constraint. Likewise, of all the disciplines represented at INED, the most successful on that count was demography. This explains the increasingly close link between population studies and demography in France. In retrospect, this identiﬁcation, which dates from the 1950s, has become the source of many anachronisms on the part of demographers who have tried to write the history of their discipline. The key to these successes lay not only in the researchers’ individual qualities. They were also due to the changes in demography at the aggregate, international level.
65To say that Henry “invented” nothing would be to succumb to the romantic vision of creation ex nihilo that has no place in the history of science. When the Trade Ministry functionary Étienne Gautier started processing the Crulai parish registers, he joined an ageless, borderless legion of anonymous investigators who had pored over the old registers. But once he sent the fruit of his labours to Louis Henry at INED, the character of his undertaking changed instantly. From a modest parish monograph, it was promoted to the rank of input for a sophisticated international discussion in a rapidly expanding discipline whose ambition was to regulate population movements on a planetary scale or at least to understand their mechanisms. The uniﬁcation of the discussion framework through the conceptual approach of analytical demography, the pre-eminence of fertility issues, the worldwide recognition that Louis Henry and INED managed to secure within a few years, their integration into a rich international institutional network where funds from U.S. foundations joined those of governments and international organizations — all of these developments propelled the Crulai family reconstitution forms to the heart of the discipline.
66At the same time, historians opened up to quantiﬁcation, recognized the importance of population issues, and progressively chose Louis Henry over his competitors or detractors from among their own number (Rosental, 1997). Louis Henry thus succeeded in bringing together a set of favourable conditions that population history had never enjoyed before him. Depending on the circumstances, the sources of population history were too fragmented, its populations too small, its approaches too national if not nationalistic, and its methods too primitive, to be credible among statisticians. Therein lies the great novelty of the Henry model and of his “historical demography”: for a while, they connected the universes of historiography, demography, and population policies. In so doing, they contributed to making demography “the” science of population in France.
AcknowledgmentsJean-Noël Biraben, Pierre Goubert, Jacqueline Hecht, Pierre Jeannin, Claude Lévy, Léon Tabah, and Pierre Vilar, as well as the late Louis Chevalier and Michel Fleury, were kind enough to grant me interviews concerning the period studied in this article: I should like to express all my gratitude for their help. I thank INED’s Director, François Héran, for allowing me access to the archives needed for my research, as well as Pierre Carouge, Dominique Chauvel-Markman, Cyrille Chareau, Cyril Le Bihan, Françoise Meunier, Adrien Minard, Patrick Rozen, and Marie Thébaud, who assisted me in my documentary and archival research. I am extremely grateful to Noël Bonneuil, who guided me in this exploration of the roots of contemporary demography, and communicated his enthusiasm for the subject to me. I have had opportunities to present a preliminary version of this study at the seminars run by Lutz Raphael at the University of Trier, and by Amy Dahan, Alain Desrosières, and Dominique Pestre at the Centre Alexandre Koyré in Paris: I thank them for their comments, and I thank the participants in my seminar at the École des Hautes Études en Sciences Sociales (EHESS) in Paris. Lastly, I am grateful to Patrice Bourdelais, Éric Brian, André Burguière, Christine Théré, and Jean-Marc Rohrbasser for reading sections of this text and offering their comments.
Sources: Fonds Louis Henry and Fonds Pierre Depoid (Centre des Archives Contemporaines).
École des Hautes Études en Sciences Sociales and Institut National d’Études Démographiques Paris.
Translated by Jonathan Mandelbaum.
On all these points, see Dupâquier (1984), Le Mée (1995), Rosental (1997), Sharlin (1977), Saito (1996), and the introduction to Viazzo (1984). The enthusiasm faded in the following decade. A victim of diminishing returns and the wider discredit attached to quantitative history, historical demography was ultimately judged to be limited and repetitive. For an early expression of these criticisms, see Burguière (1974).
An article published later (Hyrenius, 1958), in English and in more propitious circumstances, retrospectively made the author (himself a continuator of German historical genealogy) a “precursor”. See his analysis in Terrisse (1975). Henry then made contact with the Swedish demographer (Fonds Henry, art. 25, letter to Hyrenius, 7 January 1959), who later visited INED.
After his marriage, Jean Bourgeois added his wife’s name to his own and became known as Bourgeois-Pichat.
On this network of École Polytechnique alumni, see Girard (1986, p. 102). On the Fondation Carrel and its “Demography” team, see Drouard (1992) and Rosental (2003).
Their main reference work was the treatise by Lotka (1934 and 1939); their basic textbook, Michel Huber’s Cours de démographie et de statistique sanitaire, published in several volumes before and after the war.
Sauvy’s eventual change of heart was reluctant (Lévy, 1990, pp. 96ff and 107ff.). Lévy (p. 125) states that Alfred Sauvy did not acknowledge a change in fertility behaviour until 1950, and believed that population growth would remain modest. For an analysis of the discussion on the statistical reality of the phenomenon and its interpretation, see Néel (1994). For a retrospective chronology of the post-war fertility recovery, see Desplanques (1988).
“We were therefore still expecting a decline in the number of births and no one would have been surprised to see it happen in 1949” (lecture of 20 March 1950, Fonds Louis Henry, art. 11).
The preparation of these reports contributed to Henry’s training. To the still novice researcher, it imposed a format and a list of characteristics deemed relevant to the description of a population. Girard (1986, p. 108) noted the parallelism between the plan that Fleury and Henry (1956) suggested to historians for their multi-secular parish monographs and the organization of the situation reports. The irony of a model for long-period history — championed by the Annales — being partly rooted in quarterly observations will be obvious.
For reasons discussed in Rosental (2003). They are related to the history of the institutionalization of demography in France since 1939, when the High Committee on Population was established. From those troubled years there emerged a small coterie of administrators (Pierre Laroque, Jacques Doublet, Emmanuel Rain) and scientiﬁc mandarins (Robert Debré, Henri Laugier) who were convinced that demography as a science would validate the appropriateness of a pronatalist policy in rational terms. Providing “a beacon for action”, in Sauvy’s famous phrase, seemed to them a natural extension of the analysis of populations.
See, for example, Sauvy (1949b) and many articles and book reviews published in Population in the late 1940s.
A good example of the Institute’s position is provided by an article collectively signed by “INED” and published in 1956 in Population under the title “La limitation des naissances en France” (Birth Control in France). Its purpose was to assess the effects on the birth rate of a gradual liberalization of the 1920 Law on the advertising and distribution of contraceptive means. The article’s approach respected the norms of scientiﬁc caution and institutional reserve, and concluded in favour of an easing of the law. At the same time, the article repeatedly took as given that a decrease in births or in the population’s reproduction rate would be an unfortunate development. The article was written by Alfred Sauvy, Alain Girard, Paul Vincent, Louis Henry, and Jean Sutter, according to a memorandum by Alfred Sauvy of 19 March 1956. INED’s director suggested that Institute researchers who disagreed with the article should be given one page in the journal to express themselves in their own names, while avoiding “religious or purely moral views” (Fonds Henry, art. 8). No staff member took up the invitation.
“Projections retained some predictive value” only for a “relatively short” period (letter of 18 February 1955 from Louis Henry to F. Closon, Director General of INSEE, Fonds Henry, art. 17).
In his letter to Hajnal, Henry describes forecasts as “basically empirical, as are the extrapolations by hunters and anti-aircraft gunners.” He counted on experience to improve their range. Hajnal’s reply is dated 25 January 1956.
In his letter to Hajnal of 29 December 1955, Louis Henry stated that since the experience of demographic phenomena “could result only from the study of the past, I believe, as you do, that one should spend more time on that study than on computing complicated projections or forecasts. Yet I am not sure that these long and apparently unproﬁtable studies are always well regarded; the quest for proﬁtability remains very strong and I fear that the desire for immediate apparent usefulness may often cause people to prefer a deluge of supposedly precise calculations to a slow elaboration of methods capable of improving actual effectiveness — but only later.”
These public lectures are worthy of interest because they spell out hypotheses, concepts, and methods that were taken for granted in the author’s scientiﬁc publications. As public speaker, Louis Henry also expounded his conception of the demographer’s profession and even his wishes for the future of the population, on which he usually remained silent in his scholarly publications.
See in particular Wicksell (1937) and the latter’s description by Ohlin (1981, 1st. ed. 1955, pp. 44ff). Corrado Gini also published papers on marital fertility (see for example Gini, 1934a and 1934b) as did Pierre Depoid for France.
The same reasoning was applied to the United States by Shryock (1950) — who confessed a forecasting error by the Bureau of the Census — and to the United Kingdom by Carr-Saunders et al. (1951) and Notestein (1949).
For Henry, “a close analysis shows that there were no solid theoretical grounds for studying the female rather than the male population” (Fonds Louis Henry, art. 11, p. 10). This view had been common since the interwar period (Lotka, 1939, p. 89; Hajnal, 1947a).
In a household that practises contraception, “what matters is neither age nor the duration of marriage, but only the number of children already born” (Henry 1954b, p. 9).
The 1930s had seen a pronounced interest in the relationship between nuptiality and economic cycles. See Thomas (1925), Glass (1937) and Ohlin (1981, 1st ed. 1955).
Thus the sessions of the 1954 World Population Conference in Rome distinguished between fertility in the industrialized countries and in the developing countries, but did not mention countries engaged in the “demographic transition” (Benjamin et al., 1955, p. 15).
Which, between the wars, was referred to as “the productivity of marriages”. See Huber (1939, pp. 106-26) and Landry (1945, pp. 360ff).
For example, the authors of the “Indianapolis survey” in the U.S. (Kiser and Whelpton, 1949; Kiser and Whelpton, 1953), and of the 1946 Family Census in the U.K. (Glass and Grebenik, 1954). Witnessing this relative scarcity, Louis Henry, ca. 1953, considered looking up Raymond Pearl’s observations on the fertility of recently married couples but abandoned the idea because they seemed biased (Fonds Henry, art. 17).
This link was developed by Lucien March (1859-1933), director of the SGF until 1920 (Desrosières, 1985; Thévenot, 1990; Carol, 1995). It was revived under the Occupation at the Fondation Carrel, whose “Regent” was interested in the subject (Rosental, 2003).
Although he noted an improvement in an article devoted — signiﬁcantly — to family statistics (Henry, 1953d). On the detailed content of family statistics by year, see Depoid, 1943, pp. 159-62; Bunle, 1937; Huber, 1939, pp. 106-26.
“It is especially when a particular change in legislation is being contemplated that the need for proper information and the gaps in existing statistics are keenly felt” (Henry, 1953d, p. 473). Henry (1951, p. 428) listed the data lacking in France for applying the tools of demographic analysis.
Concurrently, Hyrenius (1948, p. 291) reached an identical conclusion after tabulating the countries where information on the fertility of couples was available.
Letter of 26 September 1953, from Louis Henry to the Norwegian Central Statistical Ofﬁce, asking for details on forthcoming yearbooks.
Letter of 31 August 1953, from Louis Henry to the Director of the United Nations Statistical Division, P.J. Loftus, on the disappearance of the table of live births by parity after the 1949-50 demographic yearbook.
However, it was only in 1954 that Louis Henry accepted that a long-term change in fertility was beyond dispute (letter from Henry to Jean Bourgeois, 6 March 1954). The conclusions of the 1954 World Population Conference show that the issue had not been settled by then. See Bulletin international des sciences sociales, 1954, no. 6, p. 769 and the discussion between E. Grebenik and Colin Clark in Benjamin et al., 1955.
Louis Henry had been using the term since at least 1950. He employed it in a talk to describe eighteenth-century France. See “Le problème démographique français,” n.d. , pp. 2-3, Fonds Henry.
“The adjective ‘natural’ is not ideal but we prefer it to ‘physiological’ since the factors inﬂuencing natural fertility are not purely physiological” (Henry, 1961, p. 81). On this point see also Leridon, 1988 and Caselli, Vallin and Wunsch, 2002, esp. part II.
(Henry 1952, p. 367; Henry 1953a, p. 143). At least three letters between the two men contained a detailed discussion of earlier articles by Gini and procedures for calculating fecundability (letters from Louis Henry, 26 March and 10 April 1952, and a reply from Gini on 31 March).
Whereas the former Fascist statistician was interested in the biological components of fertility as measures of the biological capabilities of populations, Pearl, at the end of his career, used them to assess the comparative efﬁciency of contraceptive practices—a crucial issue in the U.S.-U.K. context of the 1930s-1950s. See Pearl, 1939.
(Henry, 1951, p. 431). Before him, Paul Vincent, his mentor in demography, had taken a close interest in the subject, in particular for the study of mothers of large families who had been awarded the Cognacq-Jay Prize.
In a letter to Frank Lorimer of 29 October 1956, Louis Henry referred to the notion of probability of conceiving, which established the link between the Anglo-American concept of pregnancy rate and the Italian concept of fecundability, to which he subscribed. For Henry, their divergence had less to do with their theoretical grounding than with “the transition from this concept to measurement; they seem to me to have been at the origin of the discussions between the Italians, particularly Gini, and the Americans; these remained sterile for lack of sufﬁciently comprehensive theoretical studies”. On the criticisms of Gini between the wars, see Ipsen, 1996 and Rosental, 2003.
Contemporary anthropology has condemned the static view underlying the notion of “customs” used by Henry and many of his contemporaries (Lorimer, 1954). This culturalism, moreover, holds as homogeneous a series of very large and diverse areas. When Henry (1947) sought points of comparison with North African fertility, he turned to Palestine, for the sole reason that it was also a Muslim country. In late 1953, Louis Henry was asked to give L. Guibourge of the Union of Family Associations (UNAF) his opinion on “the inﬂuence of family allowances on the Muslim population of Algeria.” For this purpose, Henry cited a local study conducted in Iran in 1950. He concluded on that basis that the Algerian populations “live in a natural [fertility] regime” and that, in consequence, it would be “utterly baseless to believe that family allowances will increase the marital fertility of the Muslim women of Algeria.” Lastly, Louis Henry tended to attribute the fertility of developing countries to cultural factors, in contrast to the economic explanation reserved for the rich countries.
Henry (1951) referred to the divide when analysing the fertility of Czechoslovakia, the only country for which he could ﬁnd statistics on legitimate births by parity and birth interval. The demographer compared the country’s regional populations with one another, then with France. He looked for constants in the birth-interval distributions of these populations, where the resort to contraception varied considerably.
In a memorandum of 22 October 1953, Henry gave Alfred Sauvy estimates of Bantu demography in South Africa. For the mortality rate, he hesitated between “that of Japan in 192630 or that of India in 1921-31”. The annual number of live births per 1,000 women aged 15-49 was, he claimed, “of the same order of magnitude as in Balkan Europe” in the late nineteenth century.
See Henry’s assessment of Henripin (1954), concerning the demography of eighteenth-century French Canadians (see below): “I became fully aware of the leap into the past that this study had made possible when, in my answer to a letter from abroad that was requesting information on natural or quasi-natural fertility, I mentioned in reverse chronological order Norway in 1875 and French Canadian marriages contracted between 1700 and 1730. Thus, until this study, there was next to nothing for the period before 1875” (Fonds Henry, art. 11, talk to a public of historians).
Goubert was close to the Sixième Section of the École Pratique des Hautes Études, where he was elected directeur d’études in 1955. See Goubert, 1996; Harding, 1983; Rosental, 1997.
See Goubert, 1982, 1st ed. 1960, pp. XLVI-LIII. The journal Bibliothèque de l’École des Chartes had published several articles on the subject since the nineteenth century (see Levron, 1959). In 1902, the Congress of Learned Societies had devoted one of its inquiries to parish registers: Henry was aware of its conclusions, thanks to a review prepared by his assistant d’Adhemar. Le Mée (1995) has analysed the role of archivists in the development of historical demography.
Letter from Louis Henry to Albert Choisy of Geneva, 26 October 1956. This cooperative effort produced a book (Henry, 1956).
For example, Louis Henry knew that, for Geneva, “the mortality study will be imprecise, but the fertility study will be good” (letter to J.M. Lechner, 17 December 1955). Likewise, the report by d’Adhemar (a copy of which survives in the Fonds Henry) asserts that the usable genealogies “are typically limited to noble or prominent families”.
For Henry, the ﬁrst in “a series of fortunate encounters that have altered my views and drawn my attention to parish registers” (Fonds Henry, lecture, n.d., art. 11).
Louis Henry, lecture, n.d., Fonds Henry, art. 11, p. 3.
Henry (1953d, p. 474) justiﬁed the use of the word “family” in preference to “couple” [ménage], which, he argued, means people “living under the same roof”.
The family reconstitution forms and the Fleury–Henry manual, however, were designed for non-specialists. Henry and Fleury had written initial form-ﬁlling guidelines in the spring of 1954, based on Fleury’s observations during the extraction of data from the Dommartin registers (letter from Louis Henry to Marcel Reinhard, 10 May 1954, Fonds Henry, art. 26).
For example, as the duration of data processing was often too long to allow the completion of a one-year university thesis (mémoire), the stock of family reconstitution forms had to be carefully managed. Until October 1958, Louis Henry had an assistant, the historian Pierre Valmary. Michel Fleury had acquired experience in teamwork organization during his spell at the Archives de la Seine immediately after World War II. He had supervised the “unemployed intellectuals” who were ﬁling the huge collection of bankruptcy ﬁles.
Abbé Hudry is one of several examples. A teacher in a private (catholic) school, Life Secretary of the Académie de la Val d’Isère, he had learned about the Henry method from an account in the Revue d’histoire économique et sociale. Having just published a demographic monograph in the Mémoires of the local history society, he wrote to Alfred Sauvy on 9 March 1956, after realizing that his “method [was] not up to par”.
For example, M. Hours of the Archives du Rhône had enlisted for Louis Henry a former lathe operator, a country priest, and a police inspector (letter of 11 January 1955). He stressed the need for a clear method to prevent them from being discouraged.
Meeting since 1953 under the chairmanship of Louis Chevalier, the Sub-Commission’s more prominent members were Marcel Reinhard, André Armengaud, and Jean Meuvret. It passed on to Louis Henry the offers of services from academics, students, and volunteers.
In addition to Marcel Reinhard, then teaching in Caen, examples include Jacques Godechot and Frédéric Mauro in Toulouse, Étienne Juillard in Nancy, and Portal and Trénard in Lille. Louis Henry also received unsolicited applications, for example from Jean Ganiage, who wrote from Beauvais on 12 December 1953. Ganiage held the agrégation in history and was on assignment from the secondary-school system to the National Centre for Scientiﬁc Research (CNRS), preparing a thesis on Tunis. He later collaborated with INED on a regular basis.
See the correspondence in which Louis Henry and Pierre Valmary gave students instructions for preparing their thesis for the diplôme d’études supérieures (DES) (Fonds Henry, art. 26).
Letter from Louis Henry to Marcel Reinhard, 22 November 1954, Fonds Henry, art. 26; letter from Marcel Reinhard to Louis Henry, 27 October 1958. Goubert (1973, p. 318) notes instead that “even at the basic maîtrise [M.A.] level, we practically have to repress demographic and para-demographic enthusiasms,” but this testimony dates from the peak period of historical demography.
In a memorandum to Alfred Sauvy of 23 September 1953, Louis Henry suggested launching a pilot survey, in particular to gauge the cost of data extraction.
The discovery in the Fonds Henry of a correspondence between Pierre Goubert and Louis Henry enables us to correct the chronology that we suggested in an earlier article (Rosental, 1997), in which we dated Pierre Goubert’s espousal of the Henry model to the late 1950s. In fact, immediately after Henry’s attacks against Goubert, the latter took steps to meet the demographer and seemed “ready to work with INED […]. But he manifestly knows little about demography” (memorandum from Henry to Alfred Sauvy, late April 1953). Goubert consulted Henry about methodological issues but rebutted Henry’s 1953 article (Goubert, 1954), after which the two resumed contacts on a regular basis. By contrast, the correspondence preserved in the Fonds Henry conﬁrms the tensions between the demographer and the historian René Baehrel. The latter’s attacks against population historians prompted historians to unite in Henry’s defense. The common front was visible at the 1963 Congress of Liège, the ﬁrst major scientiﬁc meeting of historical demographers (see Actes du colloque international de démographie historique de Liège, 1963, esp. pp. 34, 45, 85, 89, 93).
From the 1980s onward, the link between the Henry method and historical demography loosened, and there has been a gradual return to a broader but less uniﬁed vision. Population history has evened the score with historical demography.
Alfred Sauvy missed no opportunity to send Louis Henry the brief notes on parish registers and other nominative sources that appeared in L’Intermédiaire des chercheurs et des curieux, a magazine for antiquarian and scholarly pursuits that Sauvy read assiduously. Above all, Sauvy allowed Louis Henry to beneﬁt from his extensive network of contacts.
Letter from Louis Henry to Abraham Stone, New York, 17 September 1954. These measures concerned female sterility, which created a bias increasingly denounced today.
Letters from Henry to Frank Lorimer, 28 September 1954 and 29 October 1956.
In a letter of March 18 1957 to Christopher Tietze, whose article on the Hutterites he had just read, Louis Henry expressed his satisfaction at the availability of precise data “on a population which is known not to practise family limitation,” as this would lessen the reservations of those who “have predetermined ideas on fertility in the absence of family limitation” and who “imagine that the lack of family limitation leads to a birth a year for most of married life; admittedly, they are historians rather than demographers”.
This subtitle refers to Fabian (1983), who explores the use of time/space correspondences in anthropology.
(Henry 1953-55, p. 33). This relationship between the western past and the non-western present being conceptualized as symmetrical, Third World demography made a reciprocal contribution to historical demography. See Louis Henry’s letter to the Indian demographer M. Sovani: “our paths converge, and I have repeatedly consulted your publications in connection with a study on the demography of a group of families of the Genevan governing class and its changes since the mid-sixteenth century”.
Letter of 25 September 1953, from Louis Henry to C.J. Martin, Director of the East African Statistical Department in Nairobi.
In 1954, using the data then available, Louis Henry compared the Scandinavia of the 1870s with Asia. Observing that Asian fertility was lower than that of Northern Europe, he assumed that “these differences may be due to biological factors, social factors, or a combination of the two. We may ask whether the importance given by European culture to the conjugal family may not have tended to increase its fertility and thus partly offset the fact that this culture tended to delay marriages” (letter to Frank Lorimer, 28 September 1954). Seven years later, Henry (1961) conﬁrmed that the differences between non-contracepting populations are signiﬁcant within Europe, but even more so with other continents.
On 25 September 1953, Louis Henry wrote to C.J. Martin (see note above) about a UN publication on the population of Tanganyika. Its completed fertility (4.4 children per woman) seemed low to him in connection with its early and high nuptiality and “marital fertility rates of the order of those of historical Europe”. Henry conducted similar correspondences with other demographers and colonial administrators.
In a letter of 25 May 1955, Louis Henry explains to L. Bastiani, Head of the General Statistical Ofﬁces of French Equatorial Africa in Brazzaville, how to estimate survival rates and “by comparing them with historical European populations, infers an order of magnitude of infant mortality”. From 1954 to 1956, Louis Henry corresponded with P. Cantrelle, Head of the Anthropology Section of the Institut Français d’Afrique Noire, which depended on the General Government of French West Africa. In a letter of 23 December 1954, Louis Henry amended the form designed by Cantrelle for the study of local fertility. He added “intermediate cells” to tabulate, in particular, the number and duration of birth intervals. Such cells turned up later in Henry’s “family reconstitution form”. Henry gave Cantrelle other advice on sampling procedures and checks on the quality of response. Other examples conﬁrm Louis Henry’s visibility as a specialist in colonial demography and the interactions with his know-how as historical demographer.
In a memorandum of 23 September 1953, Louis Henry informed Alfred Sauvy that M.L. Diaz-Gonzalez, of UNESCO’s Social Sciences Department, had “hinted that the subject might interest UNESCO and that the organization might include it in its 1955-56 programme”. In a letter of 26 June 1956 to Charles Braibant, Head of the French National Archives, to whom he was sending a copy of the Fleury–Henry Manual, Alfred Sauvy wrote: “Incidentally, a committee of United Nations experts meeting in Paris and New York in February 1954 has issued a special recommendation to governments to study the history of European populations at the start of economic development”.
From the ﬁrst quarter of 1956 to spring 1957, Jean Bourgeois-Pichat, then assigned to the UN, regularly asked Louis Henry for his opinion on a survey conducted in partnership with the Population Division in the Indian state of Mysore. Everyone was aware that Henry’s knowhow derived from his experience as historical demographer (Fonds Louis Henry, art. 17).
In a letter to Frank Lorimer of 29 October 1956, Louis Henry wrote: “[Work on historical data] has strongly inﬂuenced my thinking; I have dealt with good-quality material, conﬁned to a narrow sample but yielding far more detailed data than modern statistics do. Later, on several occasions, I had to analyse the signiﬁcance of the results and perform statistical tests. That’s fairly exceptional in current demography, where one works on large groups. I’ve also had the opportunity to push the analysis further than one usually can. I realized that even with small numbers one often obtains signiﬁcant differences; the drawbacks of small samples are more moderate than I thought, whereas their advantages exceed what I could have hoped for. […] By pushing the analysis beyond the usual practice, I’ve encountered difﬁculties of interpretation; to try to overcome them I’ve had to resort to mathematics; the importance of theoretical analysis seems even greater to me than before”.
See the article entitled “L’INED doit-il être réformé?” (“Should INED be reformed?”), Le Monde, 23 January 1971.
List of 26 October 1956, Fonds Henry, art. 17.
(Notestein, 1982; Sauvy, 1947; Sauvy, 1949a; Tabah and Sauvy, 1954). The preliminary discussions at the 1954 World Population Conference ofﬁcially referred to these categories (science and politics, intellectual rigour, or effective inﬂuence of the commission) (Bulletin international des sciences sociales, 1954, no. 4; Eugenics Quarterly 1954, no. 2). Tabah and Sauvy (1954) were apprehensive about the possibility that “the fear of lapsing into political quarrels and losing their objectivity would lead scientists to conﬁne themselves to abstract issues, thereby sacriﬁcing the true objective, namely, improving the human lot”.
Derived from the work of Frank Notestein and Kingsley Davis, transition theory elevated general empirical trends to the status of law. Between the wars, many authors — including Adolphe Landry in France—had developed a similar scenario (see Szreter, 1993, note 16, p. 694, who also expresses surprise that the theory has survived its many refutations).
Alfred Sauvy saw this attitude as a sign of the economic vigour of the socialist countries, and predicted their economic victory over the United States. Aron (1983, vol. II, p. 429), in retrospect, thought it would be “cruel to reproduce” the assertions that accompanied this forecast (“Communism is an immense test of truth in the long term and of freedom on the installment plan”).
See the account by P.R. Cox in the article by Benjamin et al., (1955), as well as Revue de l’Institut international de statistique, 1954, no. 1-3. The UN also played a major role through its statistical publications.
This notion was consistent with Alfred Sauvy’s proposals in Landry, 1945, pp. 382ff, and the emergence of psychosociology as an adjunct to demography (Girard and Henry, 1956). Greenhalgh (1996, p. 40) analyses this transition from culturalist and globalizing approaches to considerations of individual usefulness.