King Gunther

Gundaharius or Gundahar (died 437), better known by his legendary names Gunther (Middle High German: Gunther) or Gunnar (Old Norse: Gunnarr), was a historical king of Burgundy in the early 5th century. Gundahar is attested as ruling his people shortly after they crossed the Rhine into Roman Gaul.
The character also became attached to other legends: most notably he is associated with Siegfried/Sigurd and Brunhild, and is implicated in Sigurd's murder. He also appears as an adversary in the legend of Walter of Aquitaine.