In this dissertation, I seek to understand why Anglo-Americans in the early Republic became preoccupied with stories about sex, especially narratives in which sex was perceived as dangerous. Historians of sexuality have identified the late eighteenth century as an important moment in the transformation of sexual ideologies. Sex became increasingly politicized and connected to ideas about nationhood and citizenship. The regulation of sex was part of a larger transition in which populations were regulated, categorized, and controlled. The Anglo-American North is a dynamic time and place to examine these larger trends - this was the time when white Americans were actively creating a national culture, one that included white people and excluded blacks and aboriginal peoples. I show that, starting in the 1770s, Anglo-Americans increasingly published stories in newspapers, magazines, and novels, in which people were punished for illicit sexual acts. I argue that this increased attention was connected to ideas of Republican virtue. Narratives of sexual danger reflected a belief that immorality would undermine the family, the basic unit of the Republic. Men and women shared in the responsibility of preserving the Republic by controlling their passions.