This book explores the transformation of political culture in northwest Spanish America during the age of the Atlantic revolutions and the subsequent period of nation building. It examines these transformations by focusing on the meaning and intellectual importance of social difference, both as a resource and as an obstacle, for diverse political and intellectual actors. Francisco A. Ortega follows key political debates in several spheres of cultural and political negotiation, including constitutional theory, social anthropology and ethnography, political economy and education. These spheres constituted intense venues of debate and creativity, as the new republics made strenuous efforts to build the material and intellectual basis of new states. The book discusses the powerful independent projects and ambitious institutional efforts within these spheres and shows how they draw from a shared Euro-American history in order to respond to the post-colonial challenge of constructing representative republics with heterogeneous populations.