Early modern rulers believed that the more subjects over whom they ruled, the more powerful they would be. Putting this axiom into effect, Louis XIV and his minister Jean-Baptiste Colbert instituted in 1666 policies designed to encourage marriage and very large families. So began a 150-year experiment in governing the reproductive process, the largest populationist initiative since the Roman Empire. This book traces the consequences of premodern pronatalism for the women, men, and government officials tasked with procreating the abundant supply of soldiers, workers and taxpayers deemed essential for France's glory. While everyone knew-in a practical rather than scientific sense-how babies were made, the notion that humans should exercise control over reproduction remained deeply controversial in a Catholic nation. Leslie Tuttle draws on archival sources to show how royal bureaucrats mobilized the limited power of the premodern state in an attempt to shape procreation in the king's interest. Married couples, it turned out, were far more likely to exercise control by limiting the size of their families. By the late eighteenth century, marriage, reproduction and family size came to be hot-button political issues, inspiring debates that helped to define the character of the modern French nation. Conceiving the Old Regime shows that France's perennial concern with population has very deep roots in its history, and demonstrates the centrality of gender and sexuality to state formation.