Where Queens Ruled: ancient DNA confirms legendary Matrilineal Celts were no exception
Unsupervised Learning: Journal Club #2
For 2025, I’m trying out a new occasional feature for paying subscribers, the Unsupervised Learning Journal Club: I’ll offer a brisk review and consideration of an interesting paper in human population genomics.
In the spirit of a conventional journal club, at the end of each post, interested subscribers can vote on next papers to review. I’m open both to covering the latest papers/preprints and reflecting back on seminal publications from across these first decades of the genomic era.
If your lab has work we might like or you otherwise want to suggest a paper for me to cover, feel free to respond to this email or comment on this post.
Free subscribers can get a sense of the format from my ungated coverage of two favorite 2024 papers:
The other man: Neanderthal findings test our power of imagination
We were selected: tracing what humans were made for
For paid subscribers, Journal Club #1:
Wealth, war and worse: plague’s ubiquity across millennia of human conquest
Unsupervised Learning Journal Club #2
Today’s paper is Continental influx and pervasive matrilocality in Iron Age Britain. It comes out of Dan Bradley’s group in the Department of Genetics, Trinity College Dublin and appeared in the January 28, 2025 issue of Nature. The first author is Lara Cassidy.
Queen Medb’s daughters
Among historic European peoples, the Irish boast some of the most extensive collections of cultural lore outlining their mythological origins, on par with the Greeks and Romans. This is largely because just as in the Mediterranean, Christianity came gradually to Ireland, and was adopted piecemeal, bottom up, in an organic process. Christianity was not concomitant with Romanization and a sharp repudiation of old ways, but a new faith that was initially integrated alongside the culture’s native traditions. Christianity brought widespread literacy, but pagan Irish beliefs faded over a span of centuries, not decades, allowing for the emerging monasteries to capture these oral traditions in print. By the time Christianity finally superseded paganism, the native Irish religion and the nation’s heathen past had already been substantially recorded for posterity.
Works like Lebor Gabála Érenn ("Book of Invasions"), the Ulster Cycle and the Fenian Cycle preserve what the pagan Irish believed about their distant past, but also reflect their worldview. Although Christian Irish monks compiled these works, clearly interpolating their own mores into ancestral legends, that archived ancient material still offers priceless glimpses into unfamiliar cultural landscapes just beyond the Greco-Roman world.
The Ulster Cycle, dating to around 2,000 years ago, depicts an Iron Age society utterly distinct from the contemporary Roman world in aspects as fundamental as gender relations. Far from token characters or passive objects, in these earliest narrative stories from Celtic societies, women feature as individuals wielding substantial power, forces to be reckoned with. A major antagonist against Cu Chulainn, the Irish Achilles, was Medb, queen of Connacht. A cunning schemer, she triggers a war with neighboring Ulster when she insists upon attaining equivalent wealth to her husband. Bothered that his head of cattle outnumber hers by one, Medb sends her armies to steal a prized stud bull from an Ulster nobleman. Also famously lusty, she has several husbands, and takes lovers while married without any compunction. The Ulster Cycle’s queen of Connacht is likely connected to the legend of Medb Lethderg, the goddess of the land associated with central Ireland’s religious site Tara, where the high kings would ceremonially marry her, thus establishing their ritual legitimacy over the island.
People today might call Medb agentic; she has full power over her own future and makes decisions to advance her own interests as a powerful, independent force in politics. But among the Celts, powerful women were not limited to the realm of mythology; when the Romans invaded Britain in the first century AD, two historically notable queens met them. In the north, the Brigantes’ ruler was queen Cartimandua, who inherited her position from her father (rather than obtaining it through marriage). An early proponent of cooperation with the Romans, Cartimandua divorced her noble husband in 51 AD to marry his armor-bearer, a commoner named Vellocatus. Though the Romans reported aristocratic Brigantes disquiet at this turn of events, the entire episode underscores Briton women’s independence and freedom. Further south, ten years later, the queen of the Iceni, Boudicca, led a violent rebellion against the Romans. That she could muster and lead a great coalition of regional allies against the occupiers further reflects women’s substantial political power among the British Celts.
These trends persisted beyond antiquity. In 848 AD, Kenneth mac Ailpin became king of the Picts, in spite of his upbringing in the western Gaelic kingdom of Dal Riata, where he was already the hereditary ruler. One argument for mac Ailpin’s legitimacy in assuming the Pictish throne, finally uniting most of Scotland under one man’s rule, was that his maternal lineage traced to the Pictish royal line, and that the Picts traditionally inherited the throne matrilineally. This is exceptional in human societies, the overwhelming majority of which are patrilineal. But it would have aligned with women’s relatively high status in Celtic culture.
But dissenting voices have long wondered whether all these legendarily powerful Celtic women were fully factual, or perhaps more a matter of Greco-Roman and Christian observers deploying a self-serving topos. Maybe these classical observers were motivated to see in northwestern Europe’s tribal societies a primitive world that needed to be brought into the mainstream of civilization. Under this reading, ancient authors' observations about women’s prominent role in a culture are unlikely to have been purely neutral judgements, but more a convenient proof of barbarian deviancy and peculiarity, in stark relief to the unquestioned patriarchal basis of their more advanced societies.
This is why Cassidy et. al’s January 2025 Continental influx and pervasive matrilocality in Iron Age Britain is so illuminating; it brings to bear the best tools of modern science, ancient DNA, genomics and statistical analysis, investigating historical and anthropological questions to an incredibly detailed and thorough extent. Using mitochondrial DNA (mtDNA), Y chromosomes, ancestral analysis and reconstruction of pedigrees, the paper finds evidence of matrilineal and matrifocal social arrangements across Iron Age Britain in the centuries before Roman conquest, where kinship groups of high status women were the central nodes around which these societies were structured.
From the perspective of ancient DNA, a major challenge in characterizing the Iron Age in Europe has always been cremation’s widespread prevalence. Unlike burials, cremations first destroy most DNA wholesale and then scatter what precious few intact strands might survive. But happily for researchers, one tribe in ancient southwest Britain, in the modern region of Dorset, the Durotriges, practiced inhumation, bequeathing posterity a rare trove of potential data. Cassidy et al. were able to obtain 57 genomes from Durotrigian burial sites.