The British census plays an unquestioned role in governance today, and the recent digitization of nineteenth century census data has allowed millions of amateur and professional researchers to visualize their national and familial past. This study tells the tangled story of how the census took shape over the early decades of its existence, developing from a simple counting of households during the Napoleonic Wars into a centralized undertaking that involved the governmental and intellectual luminaries of Victorian Britain. Along the way, the census intertwined with the pressing questions of the day, including Malthusianism, industrialization, political representation, Irish immigration, women’s employment, reproduction, and empire. The book explores the hotly disputed process by which the census was created and developed and examines how a wide cast of characters, including statisticians, novelists, national and local officials, political and social reformers, and journalists responded to and used the idea of a census. It shows that the act of describing British society in statistical terms was also an act of contestation.