Hydraulic Societies explores the linked themes of water, power, state-building, and hydraulic control. Bringing together a range of ecological, geographical, chronological, and methodological perspectives, the essays address how humans have long harnessed water and sought to contain its destructive power for political, economic, and social ends. Water defines every aspect of life and remains at the center of human activity: in irrigation and agriculture, waste and sanitation, drinking and disease, floods and droughts, religious beliefs and practices, fishing and aquaculture, travel and discovery, water pollution and conservation, boundaries and borders, politics and economic life, wars and diplomacy, scientific study, and multipurpose dam building. From the earliest large irrigation works thousands of years ago, control over water has involved control over people, as the essays in this volume reflect. The intersections of water and power historically span international as well as domestic politics and operate at scales ranging from the local to the global. The authors consider the role of water in national development schemes, water distribution as a tool of political power, international disputes over waterways and water supplies, and the place of water in armed conflicts. They explore the ways in which political power and social hierarchies have themselves been defined and redefined by water and its control, how state leaders legitimized their rule both culturally and economically through the control of water, and how water management schemes were a means to impose and refine colonial power.