Genetic insights into the social organisation of the Avar period elite in the 7th century AD Carpathian Basin

Abstract

After 568 AD the Avars settled in the Carpathian Basin and founded the Avar Qaganate that was an important power in Central Europe until the 9th century. Part of the Avar society was probably of Asian origin; however, the localisation of their homeland is hampered by the scarcity of historical and archaeological data. Here, we study mitogenome and Y chromosomal variability of twenty-six individuals, a number of them representing a well-characterised elite group buried at the centre of the Carpathian Basin more than a century after the Avar conquest. The studied group has maternal and paternal genetic affinities to several ancient and modern East-Central Asian populations. The majority of the mitochondrial DNA variability represents Asian haplogroups (C, D, F, M, R, Y and Z). The Y-STR variability of the analysed elite males belongs only to five lineages, three N-Tat with mostly Asian parallels and two Q haplotypes. The homogeneity of the Y chromosomes reveals paternal kinship as a cohesive force in the organisation of the Avar elite strata on both social and territorial level. Our results indicate that the Avar elite arrived in the Carpathian Basin as a group of families, and remained mostly endogamous for several generations after the conquest. The Carpathian Basin in East-Central Europe is generally regarded as the westernmost point of the Eurasian steppe, and as such, its history was often influenced by the movements of nomadic people of eastern origin. After 568 AD, the Avars settled in the Carpathian Basin and founded their empire which was a powerful player in the geopolitical arena of Central and Eastern Europe for a quarter of a millennium 1,2. The hypothesis of the Asian origin of the Avars appeared as early as the 18th century. Since then various research approaches emerged indicating different regions as their home of origin: i.e. Central or East-Central Asia (see SI chapter 1b for explanation of this geographic term). This debate remained unresolved, however a rising number of evidences points towards the latter one 1,2. The history of the Avars is known from external, mainly Byzantine written accounts of diplomatic and historical character focusing on certain events and important people for the Byzantine Empire. As an example, the description of a Byzantine diplomatic mission in 569-570 AD visiting the Western Turkic Qaganate in Central Asia, claimed that their ruler complained about the escape of his subjects, the Avars 2-4. The linguistic data concerning the Avars are limited to a handful of personal names and titles (Qagan, Bayan, Yugurrus, Tarkhan, etc.) mostly of East-Central Asian origin, known from the same Byzantine written accounts.

Mitochondrial DNA Profiles of Individuals from a 12th Century Necropolis in Feldioara (Transylvania)

“…On PC1, the Avar elite group derived from the center of the Carpathian Basin (HUN_Avar-elite) is located in a marginal position. This is somehow expected as the gene pool of this group is dominated by a varied spectrum of Asian haplogroups [ 31 ]. Similarly, two isolated groups are revealed also on PC2 due to the contribution of N, R, and U suclades: a mid-Byzantine population from southwestern Anatolia (TUR_Byz) and a medieval population from southeastern Romania (seROU_med).…”

“…The resulting datasets, one consisting of 21 historical populations (including the population considered in this study) and one, including 35 modern Eurasian populations, were used for haplogroup-based analysis, as well as for sequence-based analysis as detailed below. The population from Feldioara were compared to an ancient dataset consisting of 747 sequences of European populations and a Byzantine group [ 27 ]: Lombards from Italy [ 28 , 29 ] and Hungary [ 29 ], Avars [ 30 , 31 , 32 ], Vikings from Norway [ 33 ] and Denmark [ 34 ], medieval Basques [ 35 ], Italians [ 36 ], Bulgarians [ 37 ], medieval population of Conquest period from Hungary [ 30 , 38 ], medieval populations from Poland [ 39 ], Slovakia [ 40 ], Iceland [ 41 ], southeastern Romania [ 20 , 42 ] and Bavaria [ 43 ]. In addition to these medieval groups, an Iron Age population attributed to Goths [ 44 ] and a population from Italy dated to the Roman period [ 45 ] were used in comparative analyses.…”

Kinship Determination in Archeological Contexts Through DNA Analysis

“…Through target enrichment strategies, it was possible to reveal the absence of maternal kinship in the Neolithic site of Çatalhöyük with the study of mtDNA whole genomes (Chylénski et al, 2019). Possible maternal and paternal relationships were found in ten necropolises of the Avar period (7th-8th century CE) in the Carpathian Basin thanks to the enrichment of whole mtDNA genomes and Y chromosome STRs amplified with AmpFLSTR Yfiler PCR Amplification Kit (Thermo Fisher Scientific) (Csàky et al, 2019). Thanks to mtDNA and nuclear SNPs enrichment, a matrilineal dynasty was found at Pueblo Bonito in Chaco Canyon, Mexico, between 800 and 1130 CE, associated with one of North America's earliest complex societies (Kennett et al, 2016).…”

Early nomads of the Eastern Steppe and their tentative connections in the West

“…Genetic study of Avars and their possible progenitor groups, such as Rourans and Xianbei, is very rare, and most studies focused on uniparental markers as in the case of Xiongnu. Recent studies on mitochondrial and Y haplogroups of Avar elites report a substantial fraction of their haplogroups with broadly eastern Eurasian origin (Csáky et al, 2020;Neparáczki et al, 2019). The vast majority of their Y chromosomes with eastern Eurasian origin belong to haplogroup N with a few of Q and C, suggesting their northern Asian origin and possibly a rather homogenous eastern source population at least with regard to the paternal ancestry (Csáky et al, 2020;Neparáczki et al, 2019).…”

“…Recent studies on mitochondrial and Y haplogroups of Avar elites report a substantial fraction of their haplogroups with broadly eastern Eurasian origin (Csáky et al, 2020;Neparáczki et al, 2019). The vast majority of their Y chromosomes with eastern Eurasian origin belong to haplogroup N with a few of Q and C, suggesting their northern Asian origin and possibly a rather homogenous eastern source population at least with regard to the paternal ancestry (Csáky et al, 2020;Neparáczki et al, 2019). The remaining haplogroups are of western Eurasian origin, implying admixture and heterogeneous origin of the Avar group, while it is beyond the resolution of uniparental markers to investigate if this genetic heterogeneity represents a socioethnic structure (e.g.…”