Secession and the civil war that followed are often regarded as having exclusively structural determinants, expressed in political cleavages. From this point of view, these events are explained, variously, by the rise of abolitionism in the North or sectionalism in the Union or some cultural attribute of the South. This focus gets us part of the way in understanding the events that led to secession, the creation of a Southern Confederacy, and civil war, but this interpretation says too little about (...) precisely how these events and processes played out. Secession occurred in time, sequentially and dynamically, with one state leading and other states following. This article offers a processual specification of the conditions of Southern secession and the creation of a Southern Confederacy. It does so by focusing on mobilization within the vanguard state, South Carolina, and the consequences of this activity for other Southern states. (shrink)