The monastery was founded in 1493 and closed in 1554, after the Lutheran Reformation. Sixty years. For those sixty years it worked as a hospital.
Among the eleven thousand finds are eighteen lancets, scalpels and needles. Pollen analysis shows that medicinal plants were grown in the garden, three of which did not grow wild in Iceland. And there are the bodies: some two hundred and ninety-five individuals, around ninety of them under eighteen.

The woman in grave 23

On a table at the National Museum of Iceland lies a skull with the vault pitted by star-shaped scars, and beside it a tibia bowed forward. She was a woman of twenty to twenty-five, buried in the cloister garden. In the catalogue she is SKR 23.
The lesions are those that palaeopathology associates with treponemal disease at the tertiary stage — probable venereal syphilis. That is the formula the specialists use, and it is more cautious than the single word: bone tells you the family of the bacterium, not its exact name. Skriðuklaustur remains the only archaeological site in Iceland where that diagnosis has been made with confidence. Before these finds, syphilis was thought to have reached the island only in modern times.
Nine cases have been identified, in an assemblage that at the time of counting numbered one hundred and ninety-eight skeletons. Eight are women. At least two show the congenital form: the disease passed from mother to foetus. The youngest was thirteen or fourteen.

A mineral the island does not have

In 2018 a team led by Joe W. Walser III measured mercury in the ribs of fifty individuals. Eleven were above the threshold. Those without infectious lesions averaged 0.190 parts per million; those with them, 0.540.
It is not contamination from the ground: the animal bones from the same excavation are all below 0.06 ppm, and so are the soil samples. That mercury was taken up by living people.
And here the research sets down the sentence that changes the meaning of everything else. There are no cinnabar deposits in Iceland. Mercury for medicinal use was therefore imported.
This is the point at which the bones stop speaking about disease and begin speaking about trade. A disease can arrive by many routes. A mineral the island does not have arrives only by ship — and ends up inside a femur, measurable in parts per million, five hundred years later.
The treatment was brutal: mercury vapour inhaled in a closed, heated room, ointments rubbed into the sores several times a day, for months or for years. Whoever administered it breathed as much of it as whoever received it.

The man who took land as payment

A document in the Diplomatarium Islandicum records a barber-surgeon paid to treat one hundred Icelanders suffering from syphilis. And there is a name: Lasarus Mattheusson, a German, brought over in 1525 at the request of Bishop Ögmundur Pálsson. For curing a hundred people he was to receive the farm of Skáney, in Borgarfjörður.
He got it. They called him Skáneyjar-Lassi. Kristjánsdóttir notes, drily, that it does not seem likely he managed to cure them all.

Two women and a man

SKR 23, the one with the pitted skull, has one of the lowest mercury concentrations in the whole cemetery: 0.069 ppm. With the disease at its third stage, she was not treated. The authors list the possibilities and choose none: she refused the treatment, did not live long enough to receive it, or died of something else.
SKR 201, another young woman, has the highest concentration of all the adults: 1.823 ppm. The lesions had perforated her palate in several places. The researchers write that it warrants consideration whether a toxic dose contributed to so early a death — in the sixteenth century the dosage was not standardised.
One untreated and one treated too much, in the same garden.
In the next case stands the third patient. Grave 130: a man somewhat over forty, the only male among the nine. He had broken his femur, and the femur had healed — but other marks on the bones say he did not live long afterwards. He had arthritis too. The mercury in his ribs stands at 0.598 ppm: above the threshold, within the moderate range. He was treated, and died anyway.

The house above the cemetery

In 1939 the writer Gunnar Gunnarsson, home in Iceland after thirty years in Denmark, had a house built at Skriðuklaustur to a design by the German architect Fritz Höger. Turf roof, concrete walls with basalt set into them. In 1948 he gave it to the state. He lived there for years, and the house is a museum today.
Under the grass, a few paces away, lay two hundred and ninety-five people. The place name had been saying so for five centuries. Nobody knew any longer where to look.

BIBLIOGRAPHY
Steinunn Kristjánsdóttir, “Icelandic Evidence for a Late-Medieval Hospital: Excavations at Skriðuklaustur”, Medieval Archaeology, vol. 54, 2010, pp. 371-381.
Steinunn Kristjánsdóttir, “The Poisoned Arrows of Amor: Cases of Syphilis from 16th-century Iceland”, Scandinavian Journal of History, vol. 36, no. 4, 2011, pp. 406-418.
Joe W. Walser III, Steinunn Kristjánsdóttir, Rebecca Gowland and Natasa Desnica, “Volcanoes, Medicine, and Monasticism: Investigating Mercury Exposure in Medieval Iceland”, International Journal of Osteoarchaeology, 2018, DOI 10.1002/oa.2712.
Diplomatarium Islandicum (Íslenzkt fornbréfasafn), vol. IX, Reykjavík, Hið íslenska bókmenntafélag, 1909, p. 290.

We are grateful to Dr Oddný Eir Ævarsdóttir, Director of The Gunnar Gunnarsson Institute, for all the explanations she provided.
For further information on the site, see: https://www.skriduklaustur.is/en/

*Board Member, SRSN (Roman Society of Natural Science)
Past Editor-in-Chief Italian Journal of Dermosurgery