Frey and Freya were Vanir deities associated with agriculture and subordinate to the warlike Aesir gods, who were associated with battle and victory. According to the myths, war had once broken out between the Aesir gods and the Vanir gods. As a part of the peace treaty there was an exchange of hostages, and Njord, Frey, and Freya left Vanaheim, the home of the Vanir, and went to live with the Aesir gods in Asgard.
In Asgard, Njord was married to Skadi, daughter of a giant named Thiassi, but according to one account, the mother of Frey and Freya was Njord's own sister, whom he had married in Vanaheim before he became a hostage.
Frey ruled the domain of elves. He had a magical horse named Blodighofi (Bloody-Hoof). He also drove a shining chariot that could travel over both air and sea, as easily at night as during the day. This chariot was drawn by a boar with golden bristles called Gullenbursti. A boar cult was thus associated with Frey; even today in Sweden a custom survives in which Yule cakes are baked in the shape of a boar. In several sources Frey is described as the ancestor of the line of Swedish kings.
Frey's magical ship, Skidbladnir, always made straight for its destination and was big enough to hold all the Aesir in their battle array, but portable enough to fold up into Frey's pocket when on land.
Frey married Gerd, daughter of the mountain giants Gymir and Aurboda, after a long bout of lovesickness. Frey had one day ventured to sit on Odin's high throne, Hlidskjalf, from which one could see everything everywhere. In faraway northern Jotunheim, the land of giants, Frey spied a large homestead belonging to Gerd's father. Frey saw Gerd walking into a building there and was overwhelmed by her beauty. He fell deeply in love and began pining desperately for Gerd. He left Odin's throne, full of grief. When he got home he would not speak or sleep or drink. Njord asked Frey's servant Skirnir to find out what was wrong with his son. Frey confessed to Skirnir that he was so full of grief for love of Gerd that he would not live much longer if he could not have her.
Skirnir agreed to go to Jotunheim and ask for Gerd's hand on Frey's behalf, if Frey would give him his sword, a magic weapon that would swing itself. Skirnir went on the errand and got Gerd to agree to marry Frey. She said she would meet Frey and marry him in a sacred wood called Barey nine nights later. When Skirnir took her reply back to Frey, his heart was filled with joy.
At the time of Ragnarok, the final battle between the gods and the forces of evil that would take place at the end of the world, Frey was destined to be one of the first gods to die; he would fight the fire giant Surt and would perish because he no longer had his magic sword