Piracy, or violent despoliation at sea, is ancient, yet it took on global dimensions after 1500. This chapter examines piratical violence as an early modern, global, cross-cultural phenomenon motivated by politics and religion as well as profit. Varieties of piracy ranged from random pillage of merchant vessels to state-sanctioned corsairing companies. Forms of violence included murder, kidnapping, enslavement, rape, battery, mutilation, impressment and forced conversion. In some regions, extortion rackets formed wherein the threat of piratical violence was offset by regular payments. Rising seaborne violence prompted consequential reactions, from naval arms races to coastal depopulation. By the eighteenth century powerful states such as Great Britain and Qing dynasty China passed harsh anti-piracy laws and outfitted navies for pirate extermination, which led to the jailing and execution of many suspects, some of them innocent. Sea sovereignty came to be defined as monopolising violence at sea and treating anyone defined as a pirate as subject to harsher laws than those applied to land thieves. By this logic, pirates were ‘enemies of humankind’.