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.

Norse, Nordic, or Scandinavian mythology, is the body of myths belonging to the North Germanic peoples, stemming from Old Norse religion and continuing after the Christianization of Scandinavia, and into the Nordic folklore of the modern period. The northernmost extension of Germanic mythology and stemming from Proto-Germanic folklore, Norse mythology consists of tales of various deities, beings, and heroes derived from numerous sources from both before and after the pagan period, including medieval manuscripts, archaeological representations, and folk tradition. The source texts mention numerous gods such as the thunder-god Thor, the raven-flanked god Odin, the goddess Freyja, and numerous other deities.