In Norse mythology, Víðarr (Old Norse, possibly "wide ruler", sometimes anglicized as Vidar, Vithar, Vidarr, and Vitharr) is a god among the Æsir associated with vengeance. Víðarr is described as the son of Odin and the jötunn Gríðr, and is foretold to avenge his father's death by killing the wolf Fenrir at Ragnarök, a conflict which he is described as surviving. Víðarr is attested in the Poetic Edda, compiled in the 13th century from earlier traditional sources, the Prose Edda, written in the 13th century by Snorri Sturluson, and is interpreted as depicted with Fenrir on the Gosforth Cross. A number of theories surround the figure, including theories around potential ritual silence and a Proto-Indo-European basis.