What distinguished the mass transatlantic migration that occurred between Columbian contact and the early nineteenth century from the movements of peoples around the globe that occurred both before and after this phenomenon? Two central distinguishing features were the large element of coercion in the movements across the early modern Atlantic world, and the central importance of identity in shaping both the direction of migration and its composition. On the first of these, coercion was a sine qua non, not only of the well-known slave trade, but also of the much smaller migrations of convicts and – given the temporary, if voluntary, signing away of the migrants' freedom – indentured servants and contract labourers. On the second, the question of who became slaves was determined by the refusal of Europeans to enslave other Europeans.