Scandinavia's 2,000-year Genetic History Explains the Viking Era to the Present
The Viking Era to the Present: A 2,000-year Genetic History of Scandinavia
A recent study, published on January 5, in the journal Cell1, documents the genetic evolution of Scandinavia over 2,000 years, from the Iron Age to the present. This historical examination of Scandinavia is based on an examination of 48 newly discovered and 249 previously published ancient human genomes that represent numerous famous archaeological sites and more than 16,500 current-day residents of Scandinavia. The new research provides information on migration patterns and gene flow during the Viking age, among other noteworthy findings (750–1050 CE). It also demonstrates that ancestries that were brought to the region during the Viking era ultimately declined for unknown reasons.
People came to Scandinavia through various channels and at various times.Levels of non-local ancestry in some locations are lower than those seen in ancient people from the Viking to Medieval periods, despite still being present in current Scandinavians. According to the patterns found in the archaeological record, non-Scandinavian ancient people may have contributed proportionately less to the gene pool in Scandinavia than they should have. But, the goal of the study was not to reconstruct Scandinavian history over time and space.
Instead, they were engaged in three distinct research that were each centered on a different archaeological site. One on the boat burials, one on the man-of-war Kronan, and one on Sandby borg. They were eventually combined into a single research on the Scandinavian demography during the past 2,000 years since it made more sense. This is because they began to observe differences in the levels and origins of non-local ancestry across the various regions when they examine the genetic affinities of the individuals from various archaeological sites, including the Vendel period boat burials, Viking period chamber burials, well-known archaeological sites like the Migration period Sandby borg ringfort, known for the massacre that took place there in 500 CE, and individuals from the 17th century royal Swedish warship Kronan.
The new objective was to study the impact of past migrations on the Scandinavian gene pool over time and space to better understand the genetic makeup of the region today. The researchers discovered regional variation in the time and volume of gene flow from three sources: the eastern Baltic, the British Irish Isles, and southern Europe, as revealed in the new study.
In contrast to eastern Baltic heritage, which is largely restricted to Gotland and central Sweden, British Irish ancestry was pervasive in Scandinavia from the Viking era. The ancestry of genomes from the Viking and Medieval times and the current levels of external ancestry in some locations show that ancient immigrants contributed proportionately less to the existing Scandinavian gene pool.
Last but not least, the findings demonstrate that a north-south genetic cline that distinguishes contemporary Scandinavians is primarily caused by varying proportions of Uralic ancestry. Additionally, it demonstrates that this cline was there during the Viking Age and possibly earlier. The authors contend that the most fascinating aspect of the data is what it reveals about the nature of the Viking era. All of Scandinavia was affected by the westward migration, while the eastward migration was sex-biased, with mostly females moving into the area. Overall, the results show a significant increase in gene flow during the Viking period, according to the researchers, and a possible bias toward females in the introduction of eastern Baltic and, to a lesser extent, British-Irish ancestries.
The gene pool in the majority of Scandinavia appears to have been permanently altered by gene flow from the British-Irish Isles during this time. Given the scale of Norse activity in the British and Irish Isles, which began in the eighth century with frequent incursions and culminated in the North Sea Empire, the private union that joined the kingdoms of Denmark, Norway, and England in the eleventh century, this is perhaps not unexpected. It's likely that those of British and Irish origin who came in Scandinavia at this time experienced a variety of situations and outcomes, from the forced migration of slaves to the voluntary immigration of more eminent persons like Christian missionaries and monks.
Overall, they claim that the evidence demonstrates how lively the Scandinavian Viking era was, with people moving around and engaging in a wide variety of activities. They intend to incorporate more genetic information in further research in an effort to understand how the ancestries that arrived during the Viking era were later diluted. On the basis of research into more extensive ancient records from the north, they also want to determine precisely when the north-south cline took shape.
It is necessary to find more pre-Viking people from north Scandinavia in order to determine when the Uralic heritage arrived in this area. Furthermore, since there are so few people with dates from 1000 BCE to zero, it will be crucial to recover ancient DNA from Scandinavian people with these chronologies in order to comprehend how this region of the world transitioned from the Bronze Age to the Iron Age.
Finally, more people from the Middle Ages to the present-day will aid in unraveling the timing and causes of a decline in the proportion of non-local ancestry in some contemporary parts of Scandinavia. Ancient genomes contain a wealth of fascinating information about our ancestry.
Rodríguez-Varela, R., Moore, K. H. S., Sunna Ebenesersdóttir, S., Kilinc, G. M., Kjellström, A., Papmehl-Dufay, L., Alfsdotter, C., Berglund, B., Alrawi, L., Kashuba, N., Sobrado, V., Lagerholm, V. K., Gilbert, E., Cavalleri, G. L., Hovig, E., Kockum, I., Olsson, T., Alfredsson, L., Hansen, T. F., … Götherström, A. (2023). The genetic history of Scandinavia from the Roman Iron Age to the present. Cell, 186(1), 32-46.e19. https://doi.org/10.1016/j.cell.2022.11.024