Ages of History

A transect, not a set of case studies

The project was not built to sequence a handful of striking finds but to assemble a continuous series through time, so that each new site can be read against what preceded and followed it in the same territory. In practice this meant three things: selecting material with a reliable archaeological context; processing it under one laboratory and bioinformatic protocol at Harvard, that is, without methodological seams between successive batches; and analysing it against a common reference panel — the Allen Ancient DNA Resource — so that the results remain comparable with the published European and Eurasian record.

The analytical set is the standard one for the field: principal component analysis for broad positioning; f3 and f4 statistics for the direction of shared drift; qpAdm for admixture modelling with quantitative proportions; DATES for admixture timing in generations; READv2 and ancIBD for kinship and shared genomic segments; uniparental markers for maternal and paternal lineages.

One caution is in order. These methods yield constraints rather than direct answers to historical questions: they can reject a model of origin, or show that a population requires more than one source, but they do not establish ethnic affiliation and they do not replace archaeological and historical argument. Source labels in the models are proxies for ancestry streams, not literal communities.

Peer-reviewed results

• Paleogenomic evidence for genetic heterogeneity and prior admixture in Gothic-associated communities of late antique Bulgaria Stamov S., Chobanov T., Wang T., Stoeva K., Momchilov D., Aladzhov A., … Heather P., Toncheva D., Zamfirov M., Lazaridis I., Reich D. (2026). Frontiers in Genetics 17, 1864752. Published 24 July 2026. doi.org/10.3389/fgene.2026.1864752

  37 individuals from Aquae Calidae and the Aul of Khan Omurtag. The two cemeteries share Gothic-associated material culture and east–west Christian burial orientation, yet they are not one genome-wide population; DATES places north–south admixture roughly 12 generations before burial, that is, before the documented Gothic settlement south of the Danube.

• Paleogenomic observations on the population of the different parts of medieval Bulgaria and its relation to present-day Balkan populations Stamov S., Chobanov T. (2025). Annual of Sofia University “St. Kliment Ohridski” — Faculty of History 108(1), 17–46. In Bulgarian. doi.org/10.60053/GSU.IF.1.108.17-46 · full text

  The project's only Bulgarian-language paper. It treats the early medieval transformation of Balkan populations as gradual integration rather than a single replacement event.

• Slavs in the closet: computational genomic analysis reveals cryptic slavic signatures in the Avar Khaganate and their contribution to medieval Croatian population formation Chobanov T., Stamov S. (2025). Frontiers in Genetics 16, 1610942. Published 22 September 2025. doi.org/10.3389/fgene.2025.1610942
• Rasho Rashev and the Sarmatian theory for the origin of Protobulgarians. New archaeological and genomic data Chobanov T., Stamov S. (2024). Studia Academica Šumenensia 11/1, 61–90. article record on CEEOL

Preprints

Both versions of the Gothic manuscript remain available on bioRxiv under the same identifier. The second is the version behind the published article; the first differs in the extent of the series, before the conservative revision of the C5 horizon.

• Paleogenomic Evidence for Genetic Heterogeneity and Prior Admixture in Gothic-Associated Communities of Late Antique Bulgaria bioRxiv, version 2, 25 March 2026. biorxiv.org — v2
• Gothic Identity as Cultural Practice: Paleogenomic Evidence for Multi-Ethnic Assemblages Under Gothic Material Culture in Late Antique Bulgaria (4th–6th centuries CE) bioRxiv, version 1, 5 March 2026. biorxiv.org — v1 · doi.org/10.64898/2026.03.03.709317

Where the genomes are

The project follows a three-tier open-data model: raw reads go to the European Nucleotide Archive; processed genotype matrices to Harvard Dataverse; the full national series with its metadata is held on the server at UNIBIT. Each set opens with the publication of the corresponding paper.

• Raw sequence data — European Nucleotide Archive Main series: PRJEB106907 Deposit for the Gothic paper: PRJEB121210 · samples ERS30837346–ERS30837354 · runs ERR17599381–ERR17599389
• Pseudo-haploid genotypes — Harvard Dataverse doi.org/10.7910/DVN/7RVV9N
• Supplement and interactive visualisations (PCA, f3, DATES, READv2) github.com/StamovS/gothic-adna-supplement
• Reference panel — Allen Ancient DNA Resource Mallick S. et al. (2024). Scientific Data 11:182. doi.org/10.1038/s41597-024-03031-7

Server and metadata base

The project's bioinformatic server is hosted at the University of Library Studies and Information Technologies (UNIBIT), Sofia. It serves three functions: a computing environment for the analyses; a national repository for the project's samples; and a metadata base of more than 1,000 records covering standardised population nomenclature, archaeological context, chronology, curating institution and laboratory identifiers.

Access is granted on request, through IBSCT–BAS or through project contributors.

Conferences

• The genetic origin of Proto-BulgariansWang T., Chobanov T., Stamov S., Rohland N., Mallick S., Lazaridis I., Reich D. — ASHG 2025, Boston.
• The Ages of History ProjectChobanov T., Stamov S. — 16th INFRAMAT, Varna, 2025.
• The Gothic Bishopric Center in North-Central BulgariaStamov S., Chobanov T. — International archaeology and paleogenomics conference, Prague–Brno, 20–22 April 2026.

Press and public presentation

• Closing press conference Bulgarian News Agency, Sofia, 19 May 2026. bta.bg
• The ancient Goths were an ethnically diverse group Marshall M., New Scientist, 16 March 2026. newscientist.com
• Interview with Assoc. Prof. Todor Chobanov on the Goths 24 Chasa daily, 19 March 2026. In Bulgarian. 24chasa.bg
• The Goths in the Balkans as a complex political coalition Paragraf.bg, 18 March 2026. In Bulgarian. paragraf.bg
• The Goths in the Bulgarian lands: a new study “Discussion Studio”, SKAT Television, April 2026 — Assoc. Prof. Todor Chobanov. In Bulgarian. recording on YouTube
• What is encoded in our genes · The Ages of History project Two-part television conversation, July 2026 — Assoc. Prof. Todor Chobanov and Svetoslav Stamov. In Bulgarian. part 1 · part 2
• Video interview U Digest, 2026. youtube.com

The contract has closed; the work has not

Funding under contract KP-06-N70/8 ended on 30 May 2026. A substantial share of the sequenced individuals remains unpublished: processing, modelling and manuscript preparation continue jointly with the Harvard team, and several separate studies are at various stages — among them a series spanning the late antique to early medieval transition on the northern Black Sea coast, and the later horizon separated out during the reassessment of the Aul of Khan Omurtag.

This matters directly to anyone considering a request: there is currently no open funded channel for new sequencing. Requests are collected, assessed and grouped so that they can be carried into a subsequent grant proposal or into an agreed quota with the partner laboratory.