Fine-scale sampling uncovers the complexity of migrations in 5th–6th century Pannonia

As the collapse of the Western Roman Empire accelerated during the 4th and 5th centuries, arriving “barbarian” groups began to establish new communities in the border provinces of the declining (and eventually former) empire. This was a time of significant cultural and political change throughout not only these border regions but Europe as a whole.1,2 To better understand post-Roman community formation in one of these key frontier zones after the collapse of the Hunnic movement, we generated new paleogenomic data for a set of 38 burials from a time series of three 5th century cemeteries3,4,5 at Lake Balaton, Hungary. We utilized a comprehensive sampling approach to characterize these cemeteries along with data from 38 additional burials from a previously published mid-6th century site6 and analyzed them alongside data from over 550 penecontemporaneous individuals.7,8,9,10,11,12,13,14,15,16,17,18,19 The range of genetic diversity in all four of these local burial communities is extensive and wider ranging than penecontemporaneous Europeans sequenced to date. Despite many commonalities in burial customs and demography, we find that there were substantial differences in genetic ancestry between the sites. We detect evidence of northern European gene flow into the Lake Balaton region. Additionally, we observe a statistically significant association between dress artifacts and genetic ancestry among 5th century genetically female burials. Our analysis shows that the formation of early Medieval communities was a multifarious process even at a local level, consisting of genetically heterogeneous groups. •Novel genomic data from 53 individuals from 5th–8th century Europe were generated•The sites exhibit significant genetic diversity comparable to large swaths of Europe•Associations between genomic ancestry and burial customs vary in the analyzed sites•Spatial modeling analyses indicate gene flow from northern Europe into Pannonia Vyas, Koncz, et al. conduct a multidisciplinary analysis of 5th–6th century communities from the territory of former Roman Pannonia. Despite archaeological similarities, they find significant differences in genomic ancestry between the sites as well as evidence of gene flow from Northern Europe into the region starting in the late 5th century.