The Holy Roman Empire lasted for over a millennium, yet its development and institutions are still commonly dismissed as largely irrelevant to broader historical issues. Recent scholarship challenges this view but until now has failed to provide a convincing interpretation of the political structure which provided the framework within which such major events as the Reformation and the Thirty Years War developed. Drawing on a wealth of specialist studies, Peter Wilson offers an alternative way of looking at the Empire, seeing it not as a failed monarchy or flawed forerunner of a later German nation-state, but on its own terms as a multi-layered structure combining monarchical, hierarchical and federal elements. Key stages in the Empire's development are explained within the context of wider European history.