After the end of the Roman era, the Anglo-Saxons are said to have arrived in Britain across the North Sea. An archaeogenetic study now sheds light on the extent of this migration. There is evidence of a surprisingly high level of immigration: it resulted in an average proportion of about 75 percent of immigrant ancestry in the early medieval population of eastern and southern England. Mixing with the local population apparently varied greatly from region to region, and social aspects are also reflected in the study results.
They came from the area that includes what is now the Netherlands, northern Germany and Denmark: from the 5th century AD, Germans from various tribes immigrated to Great Britain, grouped under the term Anglo-Saxons. This is reported in historical records and is also reflected in cultural developments on the island. This story has been studied by many archaeologists, historians, linguists and geneticists. However, there is still a lack of clarity about the extent of this migration and what significance it had.
The researchers led by Joscha Gretzinger from the Max Planck Institute for Evolutionary Anthropology in Leipzig have now investigated these questions using archaeogenetic methods. The concept is based on the analysis of DNA obtained from finds of human remains. As part of their study, the scientists analyzed and compared 278 ancient genomes from England and hundreds of DNA samples from continental Europe. This genetic information came from skeletons of people who lived between 200 and 1300 AD.
Extensive immigration
The results of the genetic investigations fundamentally show that the early medieval population in eastern and southern England was strongly influenced by migration: immigration led to an average genetic heritage of which around 75 percent could be traced back to people from continental Europe. "Not only did we get an idea of the scale of migration, but also how it affected communities and families," says Gretzinger. In the case of an Anglo-Saxon burial ground at Buckland near Dover, for example, the scientists were able to reconstruct a family tree spanning at least four generations. This identified the point in time at which migrants and the previously native Romance-British population had mixed.
However, as the team further reports, there are clear regional characteristics in England during the merger process. "We found some significant differences in how this migration affected communities," says co-author Duncan Sayer of the University of Central Lancashire. “In some places we are seeing clear signs of active integration between natives and immigrants, as in the case of Buckland near Dover or Oakington in Cambridgeshire. In other cases, however, such as at Apple Down in West Sussex, people of immigrant and native ancestry were buried separately in the local cemetery. Perhaps this is evidence of a certain social separation between the two groups at this location,” says Sayer.
combination with archaeological findings
The international and interdisciplinary research team was also able to link the genetic information with archaeological findings. It was found that in the cemeteries examined, both people with a native and a migrant background were buried in elite graves during the transitional period. In detail, however, it became clear that Anglo-Saxon women were more often equipped with grave goods such as jewelry than women of local origin. Men buried with weapons, on the other hand, are about equally likely to come from a migrant or native background.
The scientists also compared the new genetic data from the early Middle Ages with genomes of today's British population. This shows that the Anglo-Saxon portion of the gene pool has declined significantly. Today, on average, only about 40 percent of English people's DNA is derived from early continental European immigrants. The researchers' comparisons revealed that 20 to 40 percent of their genetic heritage may be due to ancestors from modern-day France or Belgium.
“It remains unclear how this additional lineage came to England. We see a kinship of this lineage with France and other countries south of the English Channel. It could be related to isolated events such as the Norman conquest of England, or it could have been the result of centuries of mobility across the English Channel," says senior author Stephan Schiffels from the Max Planck Institute for Evolutionary Anthropology. "Future work that specifically targets the Middle Ages and subsequent time periods will be able to uncover the nature of this additional genetic signal in the future," the scientist hopes.
Source: Max Planck Institute for Evolutionary Anthropology, Article: Nature, doi: 10.1038/s41586-022-05247-2