AD 400-800 Early medieval

During this period Rome’s military power could no longer maintain its empire intact in the west. As a result of either Roman influence or Roman military threat, Germanic peoples had long since organised themselves into relatively large political groupings. Now they founded kingdoms in the west, often with the grudging agreement of the Roman authorities and in cooperation with the existing aristocracy: Franks and Burgundians in western Europe, Anglo-Saxons in Britain, Ostrogoths in Italy and Visigoths in Spain. Some of them acknowledged the notional authority of the eastern Roman emperor, who ruled his still powerful state from Constantinople (Byzantium).

Although most of northern and eastern Europe remained pagan, the groups who founded these new kingdoms (with the exception of the Anglo-Saxons) were already Christianised. However, most had been converted to heretical Arian Christianity and only gradually converted to the orthodox theology of Rome and Constantinople. These new kingdoms could be fragile, as they fought among themselves or submitted to revived Byzantine power, like Ostrogothic Italy in the 6th century AD, to or the new power of Muslim Arabs, like Visigothic Spain in the 8th century. By the 8th century the Franks were dominant in the west, symbolised by the coronation of the Frankish king Charlemagne as ‘Roman Emperor’ by the Pope in AD 800.