A study published in the journal Royal Society Open Science unveiled that some medieval manuscripts from European abbeys were bound using sealskin. DNA analysis conducted on these manuscripts revealed that the skins used belonged to seals hunted in the 12th and 13th centuries.
An international group of scientists from France, the United Kingdom, and Denmark analyzed 32 medieval books using biocodicological analyses to understand the biological information preserved in the books. Focusing on 19 books created between 1140 and 1275, the experts used mass spectrometry and ancient DNA analysis to determine the materials used in the bindings.
The analyses revealed that these 19 books were all bound with skin from pinnipeds, a group that includes seals. Specifically, the skins were identified as coming from harbor seals, harp seals, and bearded seals. These findings contradict the previous belief that medieval book bindings were made exclusively from the skins of domestic animals.
"The distinctive white, furry bindings may therefore have been appreciated solely for their visual and environmental qualities—they're waterproof—rather than for any knowledge of their zoological and geographical origin," said Élodie Lévêque, the study's lead author and an expert in book conservation at Paris 1 Panthéon-Sorbonne University, according to Live Science.
The sealskin bindings suggest a medieval trade network that extended well beyond local sourcing. The researchers were able to tell that the seals came from a surprisingly diverse geographic area, including Scandinavia, Denmark, Scotland, and either Greenland or Iceland. This indicates that the Norse descendants of the Vikings traded seal skins from these regions to mainland Europe.
French monks likely did not know the origin of the material used for the bindings, as there was no word for "seal" in Old French. The Cistercian monks described seals as the "sea calf," and there is no existing written record of the purchase or any use of sealskin at Clairvaux Abbey.
The use of sealskin in bindings appears to have ended just before 1300, despite its practicality as a durable, waterproof material that retains a presentable appearance for decades. Researchers suspect this could be due to the Little Ice Age, which caused Norse settlements to disappear from Greenland. "Norse hunting methods in the Arctic were not well suited to the increased sea ice resulting from climate change," scientists wrote, according to The Independent.
This discovery refutes previous beliefs about bookbinding in the Middle Ages, demonstrating the interconnectedness of medieval societies and the reach of their trade networks. Skins were delivered from Greenland, Iceland, and Scandinavia to France, England, and Belgium.
The article was written with the assistance of a news analysis system.