The chapters in this volume clarify the notion of political identity by focusing on the metaphysics of polities. By analysing the notion of political identity, they provide the conceptual resources for a deeper understanding of the theoretical and practical debates on populism, the crisis of sovereignty, the feasibility of a world government, and ethical, religious, and cultural pluralism. What is a political community? Any answer to this question lies at the intersection between three fields: metaphysics, philosophy of action, and political philosophy. The question concerns how and why a plurality of individuals becomes a political unity, what principles or forces keep that unity together, and what threats that unity can encounter. In this volume, the contributors investigate how different metanormative views affect the possible answers to this metaphysical question. They explore the role that the individual identities of agents play in grounding common practices that underpin political life. They investigate the individual identities of agents as the result of the interplay between natural and cultural factors. Finally, they observe the ways in which a political community, as a collection of individuals who hang together in an attempt to reach common purposes, demonstrate a certain metaphysical solidity. Political Identity and the Metaphysics of Polities will appeal to researchers and advanced students working in metaphysics, political philosophy, political theory, and philosophy of action.