Odin, Vili, and Ve had created the universe out of the remains of Ymir and had killed almost every living giant in the process. Through these acts, they had shown that they were capable of grand feats of both creation and destruction.
Creation of men
The brothers were wandering around in Midgard, soaking in the pristine images of the world that they had created. During one of their walks, they came across two tree logs, one from an ash tree and one from an elm tree. The ash tree was strong, its bark was tough and its trunk was unrelenting. The elm tree was beautiful, its branches were supple and graceful. These were fine construction materials indeed. And so the gods started to create humans.
We have already explained how the brothers had created the race of dwarfs by bestowing intelligence on giant maggots. It pleases us to learn that they took a slightly different course of action when they decided to create mankind.
Odin picked up the logs and gave them life and a soul. Vili picked up the logs and give them intelligence and will. Ve picked up the logs and gave them their human appearance. They named the first man, who had been the ash tree only moments ago, Ask. The elm tree had turned into the first woman and was named Embla. And thus the first couple was born, the ancestors to which we can all trace back our lineage.
For those of you familiar with Scandinavian mythology, you will know that Odin is often titled the Allfather. Yet humankind would have been trees if it were not for Vili and Ve. Living trees and with a soul, yes, but still trees. Thank god(s) that Vili and Ve were there.
A rupture in the brotherhood
Soon after the creation of Ask and Embla, Vili and Ve decided to break with Odin. The reason was a difference in how to proceed with the creation process. As far as the two brothers were concerned, they thought that the creation had been completed. Odin disagreed. It came to an argument (maybe even a fight?) and the brothers stormed off in their own directions.
The families of the gods
Vili and Ve took off to a realm of their own: Vanaheim, the realm of the Vanir gods. The Vanir are the gods that descend from Vili and Ve. They are the gods of peace, fertility, magic, and benevolence. They were the lords and ladies of the earth and water. Famous Vanir included Njord (god of the seas, fishing, and seafaring) and his children, Freyja (goddess of love, beauty, and magic) and Freyr (god of peace and fertility). More oft as not, Nordic tribes that lived close to the water would dedicate their worship to the Vanir gods.
Odin would settle in Asgard, the realm of the Aesir gods. The Aesir gods are the gods that descend from Odin. They were the crude counterparts of the Vanir, being the gods of war, death, power, and destruction. They were the lords and ladies of the sky. Famous Aesir include Thor (the god of thunder, strength, and holiness) and Baldr (the god of beauty, sunlight, and summer).
Introduction of magic
Being gods, the Aesir had few things that they did not possess. Yet, magic was something that did not exist in Asgard. So when a mighty völva (witch) appeared at their court, they were curious to see the power of magic. Völva could alter fate, after all. The gods knew that they would be doomed in Ragnarok, the ultimate fate in which many of them would die. Maybe magic could help them alter their fate.
Apparently, the völva could not help them alter the fate of Ragnarok, because the Aesir thrusted spears into her and burned her alive. When she resurrected herself, the gods tried to burn her again. And again, when she was reborn after that. Little did they know that this was not just any völva, but it was actually Freyja, one of the Vanir goddesses. So Freyja escaped and thus began the war between the Aesir and the Vanir.
Although the Aesir were the gods of destruction and might, the Vanir would prove to be worthy opponents. They sure tried, as they even invaded Vanaheim and tried to eradicate the rival family once and for all. Perhaps Odin forgot to mention that these were the people of his brothers. Perhaps Odin wanted to eradicate his crimes of the past once and for all. Most likely, Odin wanted to obtain all knowledge that the Vanir possessed, including the knowledge of magic. Neither side would win this war. This is something that both sides soon realized. If neither side was going to win the war, neither side was willing to spend effort (and lives) on it either.
So a truce was established between the two families. They decided to exchange hostages to seal the deal. Both families would have to put forward some of their best and brightest. These hostages would live their lives as part of the other families, taking key positions in both Asgard and Vanaheim.
An exchange of hostages
The Vanir sent Njord, Freyja, and Freyr to live in Asgard among the Aesir. These were some of their finest gods, and their arrival was welcomed by many. The Aesir sent Hoenir and Mimir. Hoenir was a formidable leader who would take over Njord’s role as chief of the Vanir. Mimir was a god that possessed great wisdom and would serve as his advisor.
So it seemed that both parties had kept their word. They had sent their best and brightest. But it was soon that the Vanir realized that they had been fooled. Hoenir proved to be a wise leader, but only if Mimir was around. If Mimir did not tell him what to say, Hoenir was just a fool. Counter to all possible forms of logic, they decapitated Mimir and sent his head back to the halls of Odin.
Yet neither side wanted to start the war all over again. Odin was even relieved: he enchanted the head of Mimir so that it would stay alive and keep advising him. The Vanir had received a bad deal, but they made it worse themselves.
Birth of Kvasir
When the two families decided that it would not prove fruitful to continue their war, they decided to end their fighting once and for all. They gathered for a feast and promised not to make war on each anymore. As a sign of their commitment to the peace, each of the gods spits into a barrel present at the feast. They used this mixture of spit to create Kvasir, who would be the wisest god of all. He would be their everlasting mediator, resolving all of their disputes. Until he got killed. But we talk about that in another story.