Density-dependent and extrinsic mortality are predicted to accelerate reproductive maturation. The first 5 years of life is a proposed sensitive period for life-history regulation. This study examines the ways in which local mortality during this sensitive period was related to subsequent marriage timing in 19^th Century Belgium (N women= 11,892; N men=14,140). Local mortality during the sensitive period was inversely associated with age at first marriage for men and women controlling for literacy, occupational status, population growth, and migration. Cox regression indicated decreased time to marriage for women (HR=1.661, 95% CI: 1.542-1.789) and men (HR=1.327, 95%CI: 1.238-1.422) from high mortality municipalities. Rising population growth rates were associated with earlier marriage for men. Migration in general was associated with later marriage for men and women. Consistent with life history predictions, harsh ecological conditions such as famine coincided with earlier marriage.

Data were collected from population censuses, statistical yearbooks and civil registers. The study population (N women= 11,892; N men= 14,140) was selected based on a database of marriage certificates from the province of Flemish Brabant (then including the capital of Brussels) from people who were born throughout Belgium between 1841-1845. Individuals were distributed equally among the birth years (each birth cohort represents around 20% of the total sample). Mortality data were collected at the municipality level from population censuses and statistical yearbooks for the period 1841-1850. We obtained the mortality data as well as figures on number of marriages between 1841-1900 and number of deaths between 1841-1850 from the Historical Databases of Local and Cadastral Statistics (LOKSTAT-POPPKAD), Ghent University, Quetelet Centre. We included women between 15-40 years and men between 15-50 years. In the following subsections, first the economic background is highlighted, and subsequently covariates are introduced.