The Norse God Víðarr | Vidar is mostly associated with the event of Ragnarök and the battle between the Aesir under the rule of Odin, and fire Jötnar giants.

Both sides are slain and only a few will survive. Víðarr is one of them, a son of Odin and member of the Aesir tribe. Víðarr is attested in the archaeological record from the Gosforth Cross dating back to the 11th Century. It depicts both the christian Judgement Day and possibly Víðarr fighting Fenrir at the event of Ragnarök. 

We learn about Vidar slaying Fenrir in the Poetic Edda, in the Völuspa poem where it says that:

‘Then comes Sigfather’s | mighty son,
Vithar, to fight | with the foaming wolf;
In the giant’s son | does he thrust his sword
Full to the heart: | his father is avenged.’ (Translation by Bellows, 1923).

Aside from that, scholars have widely debated his role and function. Virtually no other information about his overall role is attested, except for his survival after Ragnarök. Indo-European scholar George Dumezil proposed a link to the Vedic Vishnu (Lindow, 2001, p. 314).

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