DNA from 142 medieval Swedes shows grave-mates were mostly unrelated

A woman who died before the age of 30 was buried at Västerhus, in Jämtland, with a scallop shell, the badge of pilgrims to Santiago de Compostela. DNA showed that her parents, her brother and two of her daughters lay elsewhere in the same cemetery, not beside her. The pattern repeated across a larger sample: of 142 medieval Swedes sequenced by a Stockholm team, grave-mates were seldom close kin.

The finding comes from a study in Science Advances led by the Centre for Palaeogenetics at Stockholm University, released in July 2026 and covered again in late September. It cuts against a common reading of excavated graves, in which an adult buried with a child is taken to be a parent.

142 genomes from three burial grounds

The Stockholm University release says the team sequenced 142 individuals, more than 60 of them children and adolescents, from three sites: Sigtuna near Stockholm, Västerhus in Jämtland and Fjälkinge in Skåne. Archaeology Magazine’s report puts the split at 74 adults and 68 children and teenagers. The people lived from the late Viking Age through the Middle Ages, and Earth.com places their deaths between about the 900s and the 1300s, in churchyards.

The paper is titled “Equal in death: Ancient genomic analysis of children’s early Christian burials” and appears in Science Advances 2026, volume 12, issue 28. Maja Krzewińska, the lead researcher at the Centre for Palaeogenetics, worked with colleagues including Anna Kjellström and Anders Götherström, all at Stockholm University. Skeletons alone cannot reliably give a child’s sex or show whether two burials were kin; the sequences did both.

Close kin were the exception in shared graves

According to Medievalists.net’s summary of the paper, 116 of the 142 individuals came from 50 graves holding more than one person. At Västerhus, only 3 of 25 such graves held first-degree relatives; at Sigtuna the figure was 2 of 16. The study treats close relatives as parents, children and siblings, and the Stockholm release reports that such ties were “surprisingly rare” among people placed in the same grave.

Who shared those graves is itself part of the result. Of 51 graves the same summary analysed for age and sex, 28 held both adults and children (54.9 percent), 12 held only children and 11 held only adults. A grave mixing adults with children is exactly the arrangement an excavator would be tempted to read as a family unit, which is why the kinship test carries weight: more than half of the graves examined had the layout of a household burial, and the DNA mostly did not back the reading.

The definition sets the scope of “unrelated” in the study’s result. The sequences show that grave-mates were mostly not parents, children or siblings of one another; they do not exclude cousins, in-laws or more distant kin sharing a plot, and none of the reports describes a search for them. The careful statement is therefore the narrower one the authors make: close family was uncommon, and what bound people into one grave was often something other than a household tie.

Krzewińska said the pattern overturns a working assumption among excavators. Adults and children sharing a grave are often presumed to be parents and children or other close relatives, yet in most cases the DNA showed otherwise, as ScienceDaily’s September 25 repost of the release records. The identified pairs were few and specific, including one sister pair and one father and son, with same-sex burial pairs predominating.

Equal treatment of children, and the explanations on offer

The same genomes revealed the children’s sex, which bones rarely do, and the result was a pattern of equal treatment. Professor Anders Götherström said the children “were not treated as a separate category,” and that “in death, they appear to have been treated according to the same social and religious principles as adult men and women.” At Västerhus, adult men and women occupied opposite sides of the cemetery, and News-Medical’s account says boys and girls followed the same divide.

Earth.com reports tentative explanations for why unrelated people shared graves: unbaptised children may have been laid with adults, or winter burials may have waited for the spring thaw before a grave could be dug and filled. The paper also acknowledges that no single rule applies everywhere, and it sets the medieval Swedish result against a Neolithic British tomb holding 27 close relatives across five generations.

Medievalists.net notes a limit: the study examined relationships within multiple burials and did not reconstruct whole cemetery populations, and larger studies are needed to test how far the pattern extends beyond these three places.

At the three sites sequenced, 116 of 142 individuals lay in shared graves, and relatives among them were the exception.

This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.

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