Nationalism has had repercussions throughout the modern era, lying at the root of wars, revolutions, and social and cultural movements. This volume analyses and compares different forms of nationalism as they originated and developed in Europe throughout the 'long nineteenth century', and offers an original and authoritative reassessment. What is a Nation? reconsiders whether the distinction between civic and ethnic identities and politics in Europe has been overstated, and whether it needs to be replaced altogether by a new set of concepts or types. This and other typologies are explored and related to complex processes of industrialization, increasing state intervention, secularization, democratization, and urbanization. Debates about citizenship, political economy, liberal institutions, socialism, empire, changes in the states system, Darwinism, high and popular culture, Romanticism, and Christianity all affected - and were affected by - discussion of nationhood and nationalist politics. By examining the significance of such controversies and institutional changes in a broader European context, together with new and systematic comparisons, this book reassesses the history of modern nationalism.