Vanir is the name of one of two races of Gods in Norse Mythology, the other being the more well known Aesir. The Vanir live in Vanaheim, also valled Vanaland. Vanaheimr, along with Asgaard, is the home of the gods in the tree of life Yggdrasil. They were considered to be the bringers of health, youth, fertility, luck and wealth, and masters of magic. They were collectively known as nature and fertility Gods and Goddesses.
Unlike the younger warrior gods of the Aesir, the Vanir were peaceable and gentle. Far more concerned with nature than with dominating. It is also said that due to their deep knowledge of the magical arts, that they also know the future. It is said that it was was Freya who taught magic to the Aesir. The Vanir were known to practice endogamy and even incest, both of which were forbidden among the Aesir.
The name “Vanir” might be derived from the old-Norse word Vinr which means “Friend.” Other theories are the Proto-Indo-European root “wen” which means “to win” or alternatively the Proto-Indo-European word “wenos” which means “lust”.
The three most idenitifiable Vanir include Njord (the god of the sea), Frey (the god of fertility), and Freya (Goddess of love, beauty and war). Other less known Vanir include Nerthus who was the wife and sister of the God Njord, Fjolnir who was the son of Frey and the Giantess Gerd, Sveigder who married Vana, Vanlade who married a daughter of the giant Snir. Other figures also have similar names and traits as Norse gods and it is possible they were also considered to be Vanir.
The Vanir waged war against the Aesir during the Aesir-Vanir war which resulted in the unification of the two into a single tribe of Gods. The two sides exchanged hostages in order to promote peace between the two races. There is, unfortunately, not much known about the Vanir of the time before the assimilation of the two races of Gods.