This interdisciplinary book straddles the fields of history, politics, religion and sociology, and medieval and modern history. Its importance lies in its contribution to arguments about the meaning and origin of nationalism, ethnicity and nationhood, and in challenging the widely-accepted "modernist" theories of Eric Hobsbawm, Benedict Anderson and others. Its argument incorporates careful analysis of English, Irish, South Slav and African examples, and suggests finally an important contract between Christianity and Islam.