Son of Niörd, the Van. He was the Scandinavian god of fertility and peace, and the dispenser of rain. Frey was the patron god of Sweden and Iceland, he rode on the boar Gullinbursti, and his sword was self-acting. (See Gerda.)
Niörd was not of the Æsir. He, with his son and daughter, presided over the sea, the clouds, the air, and water generally. They belonged to the Vanir.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
More on Frey from Infoplease: