
Originally Posted by
BBC
Scientists believe a small population of migrants from Germany, Holland and Denmark established a segregated society when they arrived in England.
The researchers think the incomers changed the local gene pool by using their economic advantage to out-breed the native population.
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Estimates range between 10,000 and 200,000 Anglo-Saxons migrating into England between 5th and 7th Century AD, compared with a native population of about two million.
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"The native Britons were genetically and culturally absorbed by the Anglo-Saxons over a period of as little as a few hundred years," Dr Thomas added.
"An initially small invading Anglo-Saxon elite could have quickly established themselves by having more children who survived to adulthood, thanks to their military power and economic advantage.
"We believe that they also prevented the native British genes getting into the Anglo-Saxon population by restricting intermarriage in a system of apartheid that left the country culturally and genetically Germanised.
"This is exactly what we see today - a population of largely Germanic genetic origin, speaking a principally German language."