In few cases do historians consider that the existing populations were driven out or killed off entirely by the new arrivals. The question of what happened to the settled and Romanized populations of the western Empire is a complex one. Romanesque architecture flourished in the early Middle Ages: Hildesheim. The term 'Dark Ages' has now fallen from favour, partly to avoid the entrenched stereotypes associated with the phrase, but partly because more recent research and archaeological findings about the period has revealed that complex cultural influences persisted throughout this period. Historically this period has been more pejoratively termed the ' Dark Ages' by some Western European historians. This era, often characterized by historians as one of dramatic population and cultural change, is sometimes referred to as the Migration Period, and as the Völkerwanderung ('wandering of the peoples') by German historians. Often now termed the Byzantine Empire, this Eastern Roman Empire was a direct continuation of the Christian Roman Empire of late antiquity. In the more developed eastern half of the empire, however, centralized institutions still continued to function, centred on the impregnably defended city of Constantinople. Where semblances of Roman governance survived, these were largely in the form of weak and isolated city governments or else regional military commanders who had turned themselves into local strongmen in the absence of central authority. By the end of the 5th Century, the institutions of the Western Roman Empire had crumbled under the pressure of these incursions. In other cases, particularly from the 4th Century onward, incursions were hostile, the land was seized and settled by force. Some of the incursions were by agreement, in which tribal groups were assigned lands to farm and settle in return for acting as allies and confederates of Rome. The Huns, Bulgars, Avars and Magyars along with a large number of Germanic and later Slavic peoples, were prominent tribal groups that migrated into Roman territory. Some of these 'barbarian' tribes rejected the classical culture of Rome, while others, like the Goths, admired and aspired to it. As the central authority of Rome faded, the imperial territories were infiltrated by succeeding waves of ' barbarian' tribal confederations.

In Western Europe from the 3rd Century onward, the political unity of the Roman Empire began to fragment. The Middle Ages are commonly referred to as the medieval period or simply medieval (sometimes spelled ' mediaeval' or, historically, ' mediæval'). These various changes all mark the beginning of the Early Modern period that preceded the Industrial Revolution. The Middle Ages of Western Europe are commonly dated from the 5th century division of the Roman Empire (into the Western Roman Empire and the Eastern Roman Empire) and the barbarian invasions until the 16th century schism of Christianity during the Protestant Reformation and the dispersal of Europeans worldwide in the start of the European overseas exploration. The Middle Ages formed the middle period in a traditional schematic division of European history into three 'ages': the classical civilization of Antiquity, the Middle Ages and Modern Times. An early medieval Frankish king depicted with the Pope, from the Sacramentary of Charles the Bald (about 870).

Middle age history