Is it possible to be a citizen of the world? Cosmopolitan thought has been at the center of recent debates surrounding human rights, legal obligations, international relations and political responsibility. Most of these debates trace their origins to the Enlightenment of the eighteenth Century or to the teaching of Greek and Roman philosophers. Medieval literary fictions and travel accounts provide us with rich contextualizations of the complexities and contradictions of cosmopolitan thought. This collection of essays uncovers a wide array of medieval writings on cosmopolitan ethics and politics, writings generally ignored or glossed over in contemporary discourse.