Cosmopolitanism in the depths of Barbaricum evidenced by archaeogenomic data from the Late Iron Age Goth community of the Masłomęcz group

Abstract Background High mobility and extensive trade and military interactions are well recognized throughout the Late Iron Age Europe. The extremely rich archaeological record for the Masłomęcz group – a Goth-associated assemblage flourishing between 2 nd and 4 th century CE in what is now eastern Poland – has long been providing evidence for their wide cross-cultural contacts. However, the extent to which these were ephemeral or involved long-term immigration and interbreeding, remained unresolved. Results Here, by obtaining archaeogenomic data from 37 burials and reanalysing published data, we provide evidence that, while the Masłomęcz group was built mostly on Scandinavian-derived ancestry it extensively assimilated individuals from diverse directions and distances, including the Baltics, the Balkans and even further into the Mediterranean, creating a highly genetically heterogenous population. Additionally, we shed more light on the burial customs of this community by finding no close kin relations within multiperson burials. Conclusions Our findings provide evidence for long-range mobility far outside the borders of the Roman Empire. The Masłomęcz group was a highly open community embracing external contacts and immigration, perhaps contradicting popular presumptions about the so-called barbarians.