This book examines John Locke as a theorist of migration, immigration, and the movement of peoples. It outlines the contours of the public discourse surrounding migration in the seventeenth century and situates Locke's in-depth involvement in these debates. The volume presents a variety of undercurrents in Locke's writing -- his ideas on populationism, naturalization, colonization and the right to withdrawal, the plight of refugees, and territorial rights -- which have great import in present-day debates about migration. Departing from the popular extant literature that sees Locke advocating for a strong right to exclude foreigners, the author proposes a Lockean theory of immigration that recognizes the fundamental right to emigrate, thus catering to an age wrought with terrorism, xenophobia and economic inequality. A unique and compelling contribution, the volume will be of great interest to scholars and researchers of political theory, political philosophy, history of international politics, international relations, international political economy, public policy, seventeenth century English history, migration and citizenship studies, and moral philosophy.