Through his foreign conquests and internal reforms, Charlemagne is a defining figure of both Western Europe and the Middle Ages. Crowned king of the Franks in 768, he expanded their kingdoms into an empire that incorporated much of western and central Europe, recreating a single Christian imperium in the heartlands of the old Western Roman empire for the first time since the decline and fall of that polity in the late fifth century AD. After his imperial coronation Charlemagne was seen as a rival, in power and majesty, of the Byzantine Emperor in Constantinople. Charlemagne's empire, and the cultural golden age that is associated with it, encouraged the formation of a common European identity. In this magisterial new study, Hywel Williams explores every facet of the rule and legacy of one of the most remarkable rulers in European history. Emperor of the West is a major contribution to early medieval history, and is essential reading for anyone interested in the wider history of Europe.