This book provides a comprehensive overview of the meaning of cosmopolitanism and world citizenship in the history of Western political thought, and in the evolution of international politics since 1500. Providing an invaluable overview of earlier political thought, recent theoretical literature and current debates, this book also discusses recent developments in international politics and transnational protest. It will be of great interest to those specialising in political theory, International Relations and peace/conflict studies. It will also interest those already acting as global citizens.