Abstract: In many countries, fertility has fallen from historically high levels to low ones, while motherhood, once early, now begins increasingly late. How these major societal changes emerged and diffused within populations remains widely debated, as answering this requires both a unifying theory and high-quality data over the long run. We propose a framework uniting these patterns into a single model with two successive innovation-diffusion processes, each proceeding through four phases and originating in wealthier populations before diffusing to lower-income ones: low fertility and delayed fertility. To test it, we reconstruct fertility rates by maternal age for 90 French regions over 1853–2023, combining newly digitized historical sources with modern civil-status data. The French experience confirms that both innovations were adopted first by high-income populations, before diffusing with a lag that reshaped inequalities at each phase. During the first transition, the total fertility rate reached 3 in the richest regions but 4.5 in the poorest by the 1890s, converging only by the 1940s. During the second, the mean age at birth has risen since 2000 twice as fast in rich as in poor regions. By 2023, with the gap still widening, France has not yet reached this transition's convergence phase.

Abstract: Geographic variation in extreme longevity remains poorly understood, largely due to the scarcity of methodologically rigorous, fine-grained analyses at the national scale. We address this question in part using French civil registration records for the 1904–1913 birth cohorts. By applying the extinct cohort method, which derives survival estimates from death records alone, we avoid reliance on census data, a source of systematic bias in analyses of extreme longevity.  We compute sex-specific Extreme Longevity Index (ELI) across 87 regions and 1,681 functional territorial units and show that the probability of surviving from birth to age 100 varies more than twofold across regions for women (from 0.89% to 2.32%) and fourfold for men (from 0.12% to 0.47%), with a geographically coherent and temporally stable pattern common to both sexes. Spatial cluster analysis further reveals twelve longevity zones whose boundaries are robust across multiple spatial weight specifications, including six high- and six low-longevity zones. Among the high-longevity zones, the Paris Area and the Low Loire Valley exhibit contrasting mortality patterns — consistent with heterogeneous frailty selection and a uniformly favourable environment, respectively — identifying the Low Loire Valley as the most compelling candidate for a genuine blue zone in metropolitan France.

Abstract: Global cities today combine economic, political, and cultural power with some of the highest levels of longevity worldwide. How these urban health advantages emerged, and whether they were shared across urban populations, remains poorly understood, as addressing this question requires a long-term and fine-grained historical perspective. We reconstruct continuous, sex-specific life tables for Paris and its 20 districts over 1881–2019, combining newly digitized historical sources with modern statistical modeling. We first challenge the notion of a city-wide “urban penalty”: by the late \nth{19} century, life expectancy at birth already exceeded the national average in several parts of the city. These differences were sharply structured by social geography: the five most affluent districts enjoyed life expectancy 11–12 years above that of the five least affluent, with disparities rooted overwhelmingly in early-life mortality. Paris thus appears as a deeply divided “longevity capital” at the end of the 19th century. Over the first half of the 20th century, within-city inequalities narrowed markedly, reaching a historical minimum. Since the 1970s, however, these gaps have widened again: by 2019, the difference in life expectancy at birth between the most and least advantaged districts reached five years among males and four years among females.

Abstract: Recent research has shown that geography is an important predictor of life expectancy at birth (e0). However, most papers have focused on place of residence at death (PoR), yet place of birth (PoB) may be a more important predictor of later mortality. To study how different measures of geography matter, we compute the first annual full lifetables by PoB for 90 French regions between 1975 and 2019 and compare them with lifetables by PoR. We show that e0 by PoR and PoB are highly correlated, but they have diverged in recent times, particularly for men, consistent with the growing importance of migration. This divergence has consequences on the trends in geographic disparities of longevity.  First, geographic disparities by PoB have continuously declined, but measured by PoR they have risen since the 1990s. Second, the French geographical income gradient - the association between regional income and e0 - was negative and became positive in the 1990s when measured by PoR. When measured by PoB, the gradient has never been positive: it was negative but is now insignificant. These results are qualitatively similar if we study life expectancy at age 50.

Abstract: This paper proposes homogeneous annual series on the income distribution of French metropolitan départements for the period 1960-69 and 1986-2018. We rely on unpublished and newly digitised archives of the French Ministry of Finance. They consist of fiscal tabulations that are a summary of households’ income tax declarations. Based on these raw sources, we interpolate the whole income distribution of French metropolitan départements after 1986. Before 1986, we need more assumptions as only households liable to French income tax filed income tax declarations at that time. We propose a methodology to estimate the number and average income of non-taxable households before 1986 that also allows us to reconstruct the income distribution of French metropolitan départements for the period 1960-69.