The war fought between the Æsir and the Vanir, which was, according to Völuspá, the first war in the world. The cause appears to have been the arrival of Gullveig among the Æsir, and who was pierced by lances in Odin's hall and thrice burned and thrice reborn. Gullveig, was also called Heiðr, was a practitioner of the magic arts, or seið. The gods went to the judgment-seats and held council whether they should avenge the crime or should receive atonement. Apparently no consensus was reached, for a war broke out:
- Broken was the outer wall
- of the Æsir's burgh.
- The Vanir, foreseeing conflict
- tramp oér the plains.
- Odin cast (his spear),
- and mid the people hurled it:
- that was the first
- warfare in the world.
Snorri Sturluson refers to a dispute between the Æsir and the Vanir in Skáldskaparmál. They established peace in which each side spat into a kettle. At the parting the gods took that peace-token and shaped thereof a man, Kvasir. Subsequent events led to the creation of the mead of poetry. In Gylfaginning, Snorri says that both sides exchanged hostages (human pledges). The Æsir delivered Hœnir, while the Vanir gave up Njörðr and his son Freyr.
The longest account of the Æsir-Vanir war is given by Snorri in Ynglinga saga. Here he says that the Æsir also sent the wise Mímir, who provided Hœnir with good advice on all occasions:
Odin went out with a great army against the Vanaland people; but they were well prepared, and defended their land; so that victory was changeable, and they ravaged the lands of each other, and did great damage. They tired of this at last, and on both sides appointed a meeting for establishing peace, made a truce, and exchanged hostages. The Vanaland people sent their best men, Njord the Rich, and his son Frey. The people of Asaland sent a man called Hone, whom they thought well suited to be a chief, as he was a stout and very handsome man; and with him they sent a man of great understanding called Mime. On the other side, the Vanaland people sent the wisest man in their community, who was called Kvase. Now, when Hone came to Vanaheim he was immediately made a chief, and Mime came to him with good counsel on all occasions. But when Hone stood in the Þings or other meetings, if Mime was not near him, and any difficult matter was laid before him, he always answered in one way — "Now let others give their advice"; so that the Vanaland people got a suspicion that the Asaland people had deceived them in the exchange of men. They took Mime, therefore, and beheaded him, and sent his head to the Asaland people. Odin took the head, smeared it with herbs so that it should not rot, and sang incantations over it. Thereby he gave it the power that it spoke to him, and discovered to him many secrets. Odin placed Njord and Frey as priests of the sacrifices, and they became Diar of the Asaland people. Njord's daughter Freya was priestess of the sacrifices, and first taught the Asaland people the magic art, as it was in use and fashion among the Vanaland people.
- Gylfaginning, 23.
- Skáldskaparmál, 1.
- Völuspá, 25-28.
- Ynglinga saga, 4.