In Norse mythology, the Æsir–Vanir War was a conflict between two groups of deities that ultimately resulted in the unification of the Æsir and the Vanir into a single pantheon. The war is an important event in Norse mythology, and the implications for the potential historicity surrounding accounts of the war are a matter of scholarly debate and discourse.
Fragmented information about the war appears in surviving sources, including Völuspá, a poem collected in the Poetic Edda in the 13th century from earlier traditional sources; in the book Skáldskaparmál in the Prose Edda, written in the 13th century by Snorri Sturluson; and in euhemerized form in the Ynglinga saga from Heimskringla, also written by Snorri Sturluson in the 13th century.
The following attestations provide information about the war:
In two stanzas of Völuspá, the war is recounted by a völva (who refers to herself here in the third person) while the god Óðinn questions her. In the first of the two stanzas, the völva says that she remembers the first war in the world, when Gullveig was stabbed with spears and then burnt three times in one of Óðinn's halls, yet that Gullveig was reborn three times. In the later stanza, the völva says that they called Gullveig Heiðr (meaning "Bright One" or potentially "Gleaming" or "Honor") whenever she came to houses, that she was a wise völva, and that she cast spells. Heiðr performed seiðr where she could, did so in a trance, and was "always the favorite of wicked women."