Wars of national secession and ethnic cleansing, based on the claims of supposedly distinct racial, ethnic, cultural, and national identities, have disfigured recent years. Probing the roots of these conflicts, this book provides the first comprehensive survey of the full range of political theories of ethnicity and nationalism. Paul Gilbert explores the role of identity in configuring contemporary states. He examines the concepts of race, ethnicity, cultural identity, and nationality, as well as the relevant political theories, including liberalism, communitarianism, and postmodernism. He also covers in depth the topics of citizenship and migration, multiculturalism and the ethics of secession. His multidisciplinary approach will be of value to those in philosophy, politics, sociology, and cultural studies.