“The overall context of the grave indicates that it was a respected person whose gender identity may well have been non-binary,” they wrote.

If the characteristics of Klinefelter syndrome were evident, Moilanen said, the person “might not have been considered strictly a female or a male in the early middle ages community. The abundant collection of objects buried in the grave is proof that the person was not only accepted, but also valued and respected.”

The finding challenges the idea that “in the ultramasculine environment of early medieval Scandinavia, men with feminine social roles and men dressing in feminine clothes were disrespected and considered shameful”, the researchers said.

The person may also have been accepted as a non-binary person “because they already had a distinctive or secured position in the community for other reasons”, the researchers said, such as coming from a wealthy or influential family or being a shaman.

Paleogeneticists and academics with expertise in ancient DNA analysis contacted by the Livescience website generally said the study was “convincing” in showing the person buried in Suontaka was likely to have been non-binary.

Archaeologists and historians also backed the findings, saying it was “exciting” to see new work engaging with questions of gender and identity. Leszek Gardeła of the National Museum of Denmark said the study showed early medieval societies “had very nuanced approaches to and understandings of gender identities”.