The 1636-1637 Pequot War and its aftermath were formative events in the making of New England and North America. The region’s first major colonial war eliminated the Pequots as a geopolitical power, opened southern New England to English domination, nearly annihilated the Pequots, and helped to establish patterns of extreme violence against Native Americans that shaped much of the continent north of Mexico. Unsurprisingly, few events in colonial North America have produced such prolonged and unresolved historical debate. This chapter will summarize the ongoing modern Pequot genocide debate, narrate the cataclysm in detail, provide quantitative estimates of its death toll, discuss dispersal and enslavement as a genocidal strategy, reevaluate colonists’ culpability, reconsider pre-genocide Pequot population estimates, and explain how this catastrophe constituted genocide under the 1948 United Nations Genocide Convention.