My dissertation examines the relationship between family networks and the developing institutions of federal and state government in the decades between the Revolution and the Civil War. My work shows that work related to the presence and performance of emotion—what I refer to as affective labor—was inseparable from the work that drove economic ventures and political fortunes. I argue that adherence to specific emotional cultures was essential in keeping such families together and in selectively extending membership in the family to non-blood related individuals. Those families and their emotional cultures were, in turn, central to the process of nation building. I focus on two large family networks – the Coles and the Camerons – which were centered in the South, but which extended throughout the country and stretched across the Atlantic. In fact, while based in the South, these families were marked by a cosmopolitan – and not a regional – sensibility. They were deeply invested in the joint project of building the United States and creating a specific image of the country at home and abroad, although they conflated that project with the interests of their own families. Their networks include national leaders: not just James Madison, but also Thomas Jefferson, James Monroe, Nicholas Biddle, and Martin Van Buren. While my emphasis is on these men, I argue that we cannot understand them or their economic and political work without considering their familial ties and, particularly, the women in their families. It was not the men alone who guided the process of building the United States; it was the family networks of which they were a part that provided the support and connections necessary to effect change. Such an approach reveals that what we often imagine as private and personal had profound implications for public policy and economic development. Consequently, such families created an interdependent relationship between their families and the state, with familial relationships providing a metaphor for the state’s interests. These familial metaphors and relationships continued to guide elite families as they struggled to negotiate the sectional conflicts that ultimately erupted in war.