In 1940, Gadevang Man was found during peat cutting in the bogs on the island of Sealand in Denmark. At his death, he was between 30 and 50 years old, and his skeleton was dated to 480-60 BC. Only the skeleton was found, and the skull provided evidence of primitive surgery.
Typically, the chemical composition of a bog will decay the bones but preserve the soft tissues creating a leathery human corpse. However, the chemistry in the bog can vary, which determines what is preserved and what will rot. Some bog bodies are found half preserved and half skeletonized. In the case of Gadevang Man, his skeleton was well preserved by the bog.
The front left parietal bone of Gadevang Man's skull was found with a large 1.2 inch diameter hole drilled through, probably from a surgical procedure known as "Trephination". Evidence of his survival of this surgery can be seen where the bone around the opening has healed over and started to regenerate (small tongue shaped piece of bone growing into the hole).
There are many other mummies with evidence of trephined skulls. Historians suggest it was a procedure for removing evil spirits from the body which could be causing headaches or epilepsy, for example. Gadevang Man, along with other prehistoric mummies, show that prehistoric peoples had some ability to practice medicine and surgery.
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