2Sam 8:12-14

12from Edom, Moab, the Ammonites, the Philistines, Amalek, and from the spoil of King Hadadezer son of Rehob of Zobah.13David won a name for himself. When he returned, he killed eighteen thousand Edomites in the Valley of Salt.14He put garrisons in Edom; throughout all Edom he put garrisons, and all the Edomites became David's servants. And the Lord gave victory to David wherever he went.