Study reveals the secrets of an early medieval burial ground in North Ostrobothnia: some of the last marine hunter-gatherers in the Baltic Sea region

November 11/2022

A new study on historical diets examined a human remains found in Suutarinniemi burial ground on Illinsaari Island in Ii, North Ostrobothnia. The study based on measuring stable light isotope ratios of bone collagen and discovered that this person's diet had mainly consisted of seals. Such diets were typical among hunter-gatherers in the Stone Age. During later periods, the seals remained hunted, but fish played the main role and seal hunting become seasonal source of livelihood.

The study also produced information on the person’s diet in their childhood and adolescence, which turned out to be very similar as in their early adult years. In terms of childhood protein intake, a diet consisting of seals reflects the foods the whole community ate, as in early childhood food is obtained from adults. Neither were significant changes in the person’s diet observed during childhood or adolescence.

Previous studies indicate that Suutarinniemi is a burial site where cultural transformation is visible. Both cremated and inhumated burials have been found in the same graves. Cremation was continuing old tradition, whereas inhumation, a new way of burying the deceased, was introduced. On this basis of archaeological discoveries, we may conclude that old customs were undergoing a peaceful transition.

The human buried at Suutarinniemi may have been one of the last hunter-gatherers with a diet based on seals in the Baltic Sea region. No indications of such a diet were found focusing on later medieval bodies buried in Hamina graveyard in Ii on the other side of the river in earlier studies. The humans in Ii Hamina graveyard were date to later period than those in Suutarinniemi. While the study provided new information on the hunter-gatherer culture, it also supported earlier observations.

The study was led by Maria Lahtinen, and it was conducted in cooperation with Jari-Matti Kuusela, PhD, archaeologist at the Provincial Museum of Lapland, and Ville Hakamäki, PhD, archaeologist at the North Karelian Museum. The findings were published in the prestigious PLOS One scientific journal. DOI:

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Maria Lahtinen-Kaislaniemi, Research Professor,