DNA Evidence Reveals Surprising Migration Patterns in Scandinavia during Viking Age

A recent study published in the journal Cell has found that the Viking period (late 8th century to mid 11th century) saw an exceptional influx of people into Scandinavia. This period of migration was greater than any other analyzed in the study. The research, which analyzed genomes from around 17,000 Scandinavian individuals, including nearly 300 from ancient burials, found that movements from western Europe impacted all of Scandinavia, while migration from the east was more localized, with peaks in the Lake Mälaren Valley and Gotland. Gene flow from southern Europe largely affected the south of Scandinavia.

Reduced Genetic Impact on Later Scandinavians

One interesting aspect of the study was that later Scandinavians did not show the same high levels of non-local ancestry present in their Viking-era counterparts. The researchers are not sure why the migrants' genetic impact was reduced in later Scandinavians, but they have several theories. One possibility is that the migrants did not have as many children as the people already living in Scandinavia. This could be because the migrants belonged to groups that did not intend to settle down in Scandinavia, such as tradespeople or diplomats, or because they belonged to groups that were not allowed to have families or children, such as slaves or priests.

Uralic Ancestry in Northern Scandinavia

The DNA of modern Scandinavians changes gradually as you travel from north to south, a genetic "cline" or gradient due to migrations into the region of people carrying shared genetic similarities known as the Uralic component. This component can be found among the Sami people, in modern Finland, some Native Americans, and some central Asian groups. The study found occasional instances of people with Uralic ancestry, mainly in northern Scandinavia, during the Viking period and medieval times. However, the Uralic influence seems to have increased after this time, as individuals from the 17th-century sample had similar levels of this ancestry to people living today.

Other Findings from the Study

The study also found that Scandinavian ancestry has a unique structure, with a higher degree of relatedness between individuals from different parts of Scandinavia compared to people from other parts of Europe. Additionally, the researchers discovered a number of previously unknown genetic links to groups in Europe and Asia, including the Sami people, the Karelians in Russia, and the Mordvins in Russia. These links provide new insights into the history and ancestry of Scandinavian people.

Conclusion

The study's findings provide a unique and detailed look at the migration patterns and ancestry of Scandinavian people during the Viking age and beyond. The researchers hope that their work will help to shed more light on the history of this fascinating period and the people who lived through it.

Journal Information: Ricardo Rodríguez-Varela et al, The genetic history of Scandinavia from the Roman Iron Age to the present, Cell (2023). DOI: 10.1016/j.cell.2022.11.024