This fourth volume in John Pocock's great sequence on Barbarism and Religion focuses on the idea of barbarism. Barbarism was central to the history of western historiography, to the history of the enlightenment, and to Edward Gibbon himself. As a concept it was deeply problematic to enlightened historians seeking to understand their own civil societies in the light of exposure to newly-discovered civilizations hitherto beyond the reach of history. The troubled relationship between philosophy and history is addressed directly in this fourth volume.