Gunther was a historical King of Burgundy in the early 5th century.
In the Nibelungenlied, Gunther is a Burgundian king once more and seeks to make Brünhild, queen of Iceland, his wife, he is only able to pass her marriage test with the aid of the hero Siegfried and his magic cloak that grants invisibility and strength. Gunther marries Brünhild but the queen refuses to consummate the marriage until she learns the truth about Siegfried whom she has become suspicious of. Again with Siegfried's help, Gunther is able to overpower his queen and her great strength is lost with consummation. Siegfried marries Gunther's sister Kriemhild. An impassioned debate between Brünhild and Kriemhild about who has a more noble husband leads to Kriemhild telling the lie that Siegfried slept with Brünhild himself, instead of Gunther, making Brünhild no better than a concubine. Brünhild is so offended that she seeks the death of Siegfried and enlists the help of Hagen/ Hagano. Gunther eventually agrees to assist in Siegfried's murder as well, though he knows Siegfried has done no wrong, after Siegfried is murdered Kriemhild plots her revenge on his killers and eventually marries Etzel. She hatches her plot and invites her brothers to a festival in Etzel's court. Hagen warns of treachery but is ultimately ignored and Gunther and his brothers travel to the court of Etzel, leaving Brünhild behind in Burgundy. There fighting breaks out between the Burgundians and the people in Etzel's court, among whom is found the Gothic king Dietrich (or Theoderic the Great) and his loyal companion Hildebrand. All of Kriemhild's brothers die until only Gunther and Hagen remain of the Burgundians. Kriemhild orders Gunther to be killed and then beheads Hagen herself before being struck down herself by Hildebrand.
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