1 Kings 11:14-16

14Then the Lord raised up an adversary against Solomon, Hadad the Edomite; he was of the 1royal line in Edom.

15For it came about, 2when David was in Edom and Joab the commander of the army had gone up to bury those killed in battle, and had 3struck and killed every male in Edom

16(for Joab and all Israel stayed there for six months, until he had eliminated every male in Edom),