Vanaheim is the realm of the Vanir, the second family of Norse gods, and its existence points to one of the most intriguing features of Norse mythology: the memory of two distinct divine races. Alongside the Aesir of Asgard (Odin, Thor, and their kin, associated with sovereignty, war, and law) stood the Vanir, gods of fertility, prosperity, the sea, and the wealth of the natural world, chief among them Njord and his children Freyr and Freyja.
The Eddas record a primeval war between the Aesir and the Vanir, the first war in the world, which ended not in conquest but in truce and the exchange of hostages: the Vanir Njord, Freyr, and Freyja came to dwell among the Aesir (where they became some of the most important and beloved of the gods), and Aesir went to the Vanir in return. Vanaheim itself remains shadowy in the sources, its location among the worlds is never fixed, and little is said of it directly, but the war and reconciliation it stands behind have long fascinated scholars, some of whom read it as a mythologized memory of the meeting of two religious cultures or the merging of two cults. Vanaheim thus embodies the layered quality of Norse belief: a divine order assembled from more than one source, its greatest fertility gods immigrants from an older world.