Esau took his wives and sons and daughters and all the members of his household, as well as his livestock and all his other animals and all the goods he had acquired in Canaan, and moved to a land some distance from his brother Jacob. Their possessions were too great for them to remain together; the land where they were staying could not support them both because of their livestock. So Esau (that is, Edom) settled in the hill country of Seir. This is the account of the family line of Esau the father of the Edomites in the hill country of Seir. Genesis 36:6-9
After their father Isaac died, the brothers Jacob and Esau buried him. Apparently there is some reconciliation between the brothers during the burial, as was also indicated at least from Esau’s side when he met Jacob returning from Paddam Aram. Still, their large possessions require more space for each family and Esau moves to Seir. While Esau is not originally an Edomite, he becomes the father of the Edomites. These are the Edomites that centuries later refused to allow Israel to pass through their land after wandering in the wilderness on their way to the Promised Land. Somehow, old seeded conflicts from hundreds of years ago surface again. Edom has become a symbol of unbelief and hostility toward God, and God has decreed wrath on Edom.