Rapid and jarring changes wracked the frontier states of Tamaulipas and Coahuila y Nuevo Leon from 1829, the date of Mexican emancipation, until 1895, when the frontier at last became incorporated into both the Mexican state and the transnational economy. My project focuses on the presence of African Americans (Afronorteamericanos) in this area to help us to understand better these changes in the North of Mexico. Their presence is significant for several reasons. First, they made up one part of a larger migration process taking place on the Mexican frontier. In the nineteenth century, this area promised liberty and social fluidity to migrants from both central Mexico and from abroad. Second, the way that Afronorteamericanos integrated into the Mexican nation illuminates the process of ethnic integration in frontier societies. The questions of whether their integration differed from other ethnic minorities at the frontier and whether an Afro-Mexican identity was even possible for these refugees informs a portion of my research. Third, Afronorteamericans were harbingers of an expanding empire of cotton and sugar closing in on the Mexican frontier in the nineteenth century from both the Caribbean and the U.S. South. I want to research how African American freedom in Mexico resisted the expansion of this empire. In my research I shall rely on extensive municipal archives looking at documents that recorded race - particularly army registers, hacienda registers, citizenship archives, baptismal records, and marriage certificates-in order to trace the African American presence in northern Mexico. These documents will also grant me an insight into how these subjects interacted with the Mexican state and local Northern Mexican cultures. We still have very little evidence of the Afronorteamericano's history at the frontier, although both Mexican and U.S. historians have long known of their existence.