Causes
A gjenganger could have several reasons to return from the afterlife. Murdered people could seldom sleep peacefully in their graves. The same went for their murderers. People who had committed suicide often came back as gjengangere, because Christian tradition held that "self-killers" were fit neither for heaven nor hell. At other times, people came back from the grave because they had left something undone. Most often they needed someone to help them do this, before they could finally be at peace.
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