"The berserkers are one of the most interesting and least understood aspects of the Viking warrior society. These were individuals who fought in such a blinding fury that they lost all sense of self and became unconscious killing machines without dis crimination.
The term berserker has a disputed derivation. It has been suggested that it comes from the term "bare-sark," meaning "bare of shirt," or without armor. Many references to the berserkers mention their lack of body armor. The other primary suggestion is "bear-sark," describing the wearing of animal skins. Bear skin would seem to be the logical choice of fur, but in some of the sagas the berserkers are called "Wolf Skins" or "wolf-coats" (ulfhedinn). The berserkers are often associated with the Norse god Odin, or Wodan, whose name possibly comes from the German "wut," meaning "rage" or "fury," and the Gothic "wods," meaning "possessed."
This kinship with the chief Norse god is illustrated in many of the legends concern ing berserkers. One is that, like Odin, they could alter their form and become animals, or at least assume wolf-like or bearlike qualities. Hrolf's Saga describes the hero Bjarki taking the shape of a bear during battle and killing more men than any five warriors. Georges Dumezil, in Gods of the Ancient Northmen (1973), describes this phenomenon as the hamnigja, the spirit or soul of the animal appearing in dreams or visions as well as (so the Vikings believed) in reality. The berserkers were also reputed to have had an immunity to weapons, either naturally or through the performance of incantations. This quality is described in many of the sagas. It could possibly be explained by the thickness of the animal skins they wore as protection or their blind rage that dulled any feeling of pain or wounding. Either way, the sight of berserker warriors receiving what should be mortal wounds and continuing to fight certainly had a strong psychological effect on their enemies…"
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Amicalement
Armand
gets medieval.