Edom is the name of the country where Esau settled. He was named Edom due to the fact that he said to his brother Jacob, “Let me eat some of that red ” (Genesis 25:30).
Esau took Mount Seir, an area southeast of the Dead Sea, from the Horites. Moses explained to the Israelites that God had given him the land and had helped him expel the Horites (Deuteronomy 2:5,22). It was a good country with fields and vineyards (Numbers 20:17).

The relationship between Esau and Jacob is typical of how the relationship between their descendants developed.

Even before the birth of the twins, God had already indicated that the older brother would serve the younger. Although Jacob had taken away the birthright and the blessing of the firstborn from Esau in a tricky way, it was still God’s plan that Esau would be subordinate to his younger brother. Unlike Ishmael, who heard as a teenager, that his younger brother Isaac was chosen by God and complied, Esau opposed and hated Jacob (Genesis 27:41). Esau wanted to be blessed, but had no remorse for his rebellious lifestyle (Hebrews 12:16-17).

Later, Esau softened toward his brother and received him warmly (Genesis 33: 4). Perhaps he realized that he had been blessed anyway. He had received land from God (Deuteronomy 2:5), possessed much cattle (Genesis 33:9, 36:6-8) and had many servants (Genesis 32: 6 speaks of 400 men, while his grandfather Abraham had 318 trained men. See Genesis 14:14). Eventually, Esau and Jacob brotherly buried their father Isaac (Genesis 35:29).

Through the course of time the Edomites mostly had a negative attitude. This is first reflected in their refusal to let Israel pass through their territory on the way to the promised land (Numbers 20:18-21). The climax was reached when the Israelites were exiled from Judea. Instead of helping them against the enemy, the Edomites were happy and turned against them (Obadiah 12-14). They even tried to take the land from them (Ezekiel 35:10).