麻豆传媒

Remains buried in two mass graves in the same cemetery in France have been identified as medieval soldiers belonging to opposing armies.

Rozenn Colleter at the French National Institute for Preventive Archaeological Research and her colleagues have identified the skeletons as belonging to soldiers who fought in the Siege of Rennes in 1491. The skeletons were found buried in a cemetery outside the Jacobin Convent in Rennes.

The researchers identified the聽skeletons by combining historical information with archaeological techniques, including genetic analysis. They found that each skeleton was male and older than聽15, with traumatic injuries including unhealed wounds to the聽skulls and upper limbs. This pointed to a burial of聽soldiers.

Radiocarbon dating placed the聽graves somewhere between the middle of the 15th century and聽the end of the 16th century. The聽team believes they contain opposing soldiers from the Siege of Rennes, a major event in the French-Breton war, which was triggered by a succession dispute.

The war ended with several treaties, and the Breton duchess Anne of Brittany married King Charles VIII of France in 1491, a crucial step towards the formation of the modern state of France.

鈥淚t鈥檚 a really nice use of the archaeological techniques to shine a light on a historic event,鈥� says Rachel Wood at the Australian National University in Canberra, who wasn鈥檛 involved in the study.

Using stable isotope analysis of teeth and bones, the researchers were able to determine where the soldiers probably spent their childhood and last years of life.

Carbon and nitrogen isotopes shed clues on people鈥檚 diet, such as聽whether they were eating marine or terrestrial foods, says Wood, while strontium isotopes indicate the underlying geology of聽a聽region.

Oxygen isotopes can reveal the type of water people drank, which differs depending on precipitation levels. And one kind of sulphur isotope varies with distance inland. 鈥淭he ocean has got a particular sulphur isotope concentration, and so if you鈥檙e by聽the coast, there鈥檚 kind of a sea spray effect,鈥� says Wood.

Oxygen, strontium and sulphur isotopes from the soldiers in the smaller grave, which contained four skeletons, suggested that they probably grew up in Brittany or returned to the region within the last few years of their life, making it likely they were soldiers allied to聽Anne of Brittany. In the larger grave, which contained at least 28聽skeletons, analysis pointed to origins in the French kingdom, suggesting they were members of聽the French Royal army (bioRxiv, doi.org/f2m4).

Despite being from opposing armies, the two graves were in close proximity to each other. The researchers note the presence of a rosary and three sets of pearls, pointing to a more careful burial, potentially by Dominican friars, than was afforded to many soldiers during war at the time.

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