1. RELIGION AND THE DECLINE OF FERTILITY IN THE NINETEENTH AND TWENTIETH CENTURIES: THE EMERGENCE OF A RESEARCH ISSUE During the last quarter of the nineteenth century, almost all European countries began to experience a decline in their fertility level. This transition was recognized as crucial almost from its inception, and provided a strong stimulus for the scientific study of fertility: until then there had been no apparent trend toward a decline in fertility (with the exception of France) and differentials in fertility had not been very conspicuous (Lorimer 1959: 142). Handbooks and articles on population – mainly of a statistical demographic nature – took up the question of falling birth rates and its causes. The bases for these studies were the routinely-collected population statistics that made it possible to observe fertility trends for administrative regions. By identifying administrative regions that differed in the timing and extent of the fertility decline, researchers hoped to find explanations for the fertility transition. Municipal statistical offices in larger cities such as Berlin, Vienna, Budapest and Amsterdam were able to obtain more diversified data than were generally collected by national agencies, and offered social scientists the opportunity to carry out more intensive investigations of “differential fertility,” that is of variations in fertility of socially defined subpopulations, or categories defined by occupation or rural/urban residence. Somewhat later, the national statistical agencies started to collect and publish comparable data at the national level.

Renzo Derosas is associate professor at the Department of History of Ca' Foscari University, Venice, where he currently teaches Economic History. He has published extensively on Italian social and demographic history, on comparative demographic history, and on historical methods.

Frans van Poppel is senior researcher at the Netherlands Interdisciplinary Demographic Institute (NIDI) in The Hague, and was associate professor at the Radboud University Nijmegen. Demographer and historian, he has published numerous articles on the population history of the Netherlands.