Genetic history of East-Central Europe in the first millennium CE

Abstract

Background The appearance of Slavs in East-Central Europe has been the subject of an over 200-year debate driven by two conflicting hypotheses. The first assumes that Slavs came to the territory of contemporary Poland no earlier than the sixth century CE; the second postulates that they already inhabited this region in the Iron Age (IA). Testing either hypothesis is not trivial given that cremation of the dead was the prevailing custom in Central Europe from the late Bronze Age until the Middle Ages (MA). Results To address this problem, we determined the genetic makeup of representatives of the IA Wielbark- and MA Slav-associated cultures from the territory of present-day Poland. The study involved 474 individuals buried in 27 cemeteries. For 197 of them, genome-wide data were obtained. We found close genetic affinities between the IA Wielbark culture-associated individuals and contemporary to them and older northern European populations. Further, we observed that the IA individuals had genetic components which were indispensable to model the MA population. Conclusions The collected data suggest that the Wielbark culture-associated IA population was formed by immigrants from the north who entered the region of contemporary Poland most likely at the beginning of the first millennium CE and mixed with autochthons. The presented results are in line with the hypothesis that assumes the genetic continuation between IA and MA periods in East-Central Europe.

High-resolution genomic ancestry reveals mobility in early medieval Europe

“…A previous study could not reject continuity in ancestry from the Wielbark-associated individuals to later medieval individuals 48 . With Twigstats’ improved power, models of continuity are strongly rejected, with no 1-source model of any preceding Iron Age or Bronze Age group providing a reasonable fit (p << 1e-33).…”

“…Our modelling supports the idea that some early Germanic-speaking groups expanded into the area between the Oder and Vistula rivers, but since a considerable proportion of burials during this period were cremations, the possible presence of individuals with other ancestries can not be strictly rejected if they were exclusively cremated (and therefore invisible in the aDNA record). A previous study could not reject continuity in ancestry from the Wielbark-associated individuals to later medieval individuals 48 . With Twigstats' improved power, models of continuity are strongly rejected, with no 1-source model of any preceding Iron Age or Bronze Age group providing a reasonable fit (p << 1e-33).…”

“…Several recent studies have documented substantial mobility and genetic diversity in these time periods, suggesting stable population structure despite high mobility 43 , and documenting genetic variation in Viking Age Scandinavia 13,44,45 , early medieval England 3,37 , early medieval Hungary 46,47 , and Iron Age and medieval Poland 48 , but largely had to resort to using high-sample size modern cohorts to build models of ancestry change through time and space. Modern populations provide ample power to detect differences, but their genetic affinity to ancient individuals may be confounded by later gene flow, i .…”

“…First, in the Middle to Late Bronze Age (1500 BC - 1000 BC), we observe a clear shift away from preceding ancestry related to Corded Ware cultures 51 ∼500CE. Second, in the 1st to 5th century CE, individuals associated with Wielbark culture 43,48 represent an additional drastic qualitative shift away from the preceding Bronze Age groups, and can only be modelled with a >75% component attributed to the Early Iron Age (EIA) Scandinavian Peninsula, with multiple individuals at ∼100% and a stronger affinity in earlier Wielbark individuals. The Wielbark archaeological complex has been associated with the Goths, a Germanic-speaking group, but this attribution has remained unclear.…”