Any thorough understanding of the modern epidemics of AIDS and tuberculosis in Haiti or elsewhere in the postcolonial world requires a thorough knowledge of history and political economy. This essay, based on over a decade of research in rural Haiti, draws on the work of Sidney Mintz and others who have linked the interpretive project of modern anthropology to a historical understanding of the largescale social and economic structures in which affliction is embedded. The emergence and persistence of these epidemics in Haiti, where they are the leading causes of youngadult death, is rooted in the enduring effects of European expansion in the New World and in the slavery and racism with which it was associated. A syncretic and properly biosocial anthropology of these and other plagues moves us beyond noting, for example, their strong association with poverty and social inequalities to an understanding of how such inequalities are embodied as differential risk for infection and, among those already infected, for adverse outcomes including death. Since these two diseases have different modes of transmission, different pathophysiologies, and different treatments, part of the interpretive task is to link such an anthropology to epidemiology and to an understanding of differential access to new diagnostic and therapeutic tools now available to the fortunate few.