Written by Lauren Robertson, Science Writer.
Researchers at the Max Planck Institute for Evolutionary Anthropology have conducted the largest early medieval population study to date, revealing incredible insights into one of the most significant population transformations in the post-Roman world.
By combining the power of genetics and archaeology, the team analysed over 400 individuals from ancient Britain, Ireland, Germany, Denmark, and the Netherlands. Their findings could impact our view of present-day English ancestry.
All roads lead to Rome?
After the end of the Roman administration in 5th Century Britain, the British Isles and Ireland underwent several cultural shifts. Post-Roman Britain underwent huge changes in material culture, architecture, manufacturing practice, cultural practice, and language. But how did migration from continental Europe contribute to this transition? This has been a topic of debate amongst archaeologists, historians, geneticists, and linguists for many years.
To find some answers, the researchers studied genome-wide medieval DNA from 460 individuals based in Northwest Europe (including 278 from England). The ancient DNA (aDNA) was extracted from the skeletal remains of individuals dated between 299-1300 CE.
They then combined this with published aDNA data from over 4,000 individuals and compiled a reference dataset of 10,176 present-day Europeans. Archaeological data added to their understanding of contemporary population dynamics in the region. Importantly, the work outlined in this study has increased the archaeogenetic record in England from 8 to 285 individuals.
A migratory mix
Their results showed that there was a significant increase in continental northern European ancestry in early medieval England, suggesting a large-scale migration across the North Sea into Britain from countries such as Germany and Denmark. In fact, up to 76% of these individuals’ ancestry could be traced to the continental North Sea zone – though there was a lot of regional variation. It appears that families bred with the existing population in Britain, but this varied from region to region and even between communities.
Intriguingly, the team also found that men buried with weapons were equally likely to be of local or immigrant ancestry, while women buried alongside grave goods were most likely immigrants.
“With 278 ancient genomes from England and hundreds more from Europe, we have now gained really fascinating insights into population-scale and individual histories during post-Roman times,” said Joscha Gretzinger, a lead author of the study. “Not only do we now have an idea of the scale of migration, but also how it played out in communities and families.”
“We see considerable variation in how this migration affected communities,” added Duncan Sayer, archaeologist from the University of Central Lancashire and another lead author of the study. “In some places, we see clear signs of active integration between locals and immigrants, as in the case of Buckland near Dover, or Oakington in Cambridgeshire. Yet in other cases, like Apple Down in West Sussex, we see that people with immigrant and local ancestry were buried separately in the cemetery. Perhaps this is evidence of some degree of social separation at this site.”
The impact on present-day English people
Modern DNA analysis showed the lasting impact of the “Anglo-Saxon” migrations on present-day Britain, with substantial (40%) northern continental ancestry still present in these samples. Besides this, the authors also unveiled a second source of ancestral DNA – from the European south and west. In Southeast England specifically, individuals showed ancestry matching modern-day western Germany, Belgium and/or France, which matches the Frankish connections seen in the archaeological record for these regions.
“It remains unclear whether this additional ancestry related to Iron Age France is connected to a few punctuated migration events, such as the Norman conquest, or whether it was the result of centuries-long mobility across the English Channel”, said Stephan Schiffels, lead senior author of the study. “Future work specifically targeting the medieval period and later will reveal the nature of this additional genetic signal.”