Anglo-Saxon invasion of Great Britain

The Anglo-Saxon settlement of Britain describes the process which changed the language and culture of most of England from Romano-British to Germanic. The Germanic-speakers in Britain, themselves of diverse origins, eventually developed a common cultural identity as Anglo-Saxons. This process occurred from the mid 5th to early 7th centuries, following the end of Roman power in Britain around the year 410. The settlement was followed by the establishment of Anglo-Saxon kingdoms in the south and east of Britain, later followed by the rest of modern England.

The available evidence includes the scanty contemporary and near-contemporary written record, and archaeological and genetic information. The few literary sources tell of hostility between incomers and natives. They describe violence, destruction, massacre and the flight of the Romano-British population. Also, it has long been supposed that the influence of Celtic languages on Old English was slight. These points have suggested a very large-scale invasion by various Germanic peoples. In this view, held by the majority of historians until the mid to late twentieth century, much of England was cleared of its prior inhabitants. If this 'traditional' viewpoint were to be correct, the genes of the later English people would have been overwhelmingly inherited from Germanic migrants.

Another view, probably the most widely held today, is that the migrants were relatively few, centred on a warrior elite. They then dominated a process of acculturation to Germanic language and material culture. Consistent with this theory, archaeologists find that settlement patterns and land-use show no clear break with the Romano-British past, though there are marked changes in material culture. This view predicts that the ancestry of the people of Anglo-Saxon and modern England would be largely derived from the native Romano-British. The uncertain results of genetic studies tend to support this prediction.

There are also two less well-supported theories, held by a minority of scholars, both originating from population genetics studies. First, Stephen Oppenheimer has argued that Germanic peoples, language and culture existed in eastern regions of Britain, even in pre-Roman times. This idea has been very actively challenged by a number of linguists. Second, that the early settlers may have arrived in considerable numbers but represented a minority relative to the natives. If these incomers established themselves as a social elite, this could have allowed them enhanced reproductive success (the so-called 'Apartheid Theory'). In this case, the genes of later Anglo-Saxon England could have been largely derived from moderate numbers of Germanic migrants.

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