Charles Ellicott Commentary Genesis 36:31

"And these are the kings that reigned in the land of Edom, before there reigned any king over the children of Israel." — Genesis 36:31 (ASV)

The kings.—In the triumphal song of Moses on the Red Sea, we still read of “dukes of Edom” (Exodus 15:15); but when Israel reached the borders of their land, we find that Edom then had a king (Numbers 20:14).

But in the list given here, no king succeeds his father. These were probably petty monarchs who sprang up in various parts of the country during a long period of civil war. In this war, the Horites were ultimately as completely conquered as the Canaanites were in Palestine under the heavy hands of Saul and Solomon.

In the time of the dukes, there were also Horite dukes of the lineage of Seir, ruling districts apparently intermingled with those governed by the descendants of Esau. But all these now disappear.