“And the king of the children of Ammon answered unto the messengers of Jephthah, Because Israel took away my land, when they came up out of Egypt, from Arnon even unto Jabbok, and unto Jordan: now therefore restore those lands again peaceably.”
King James Version (KJV)
11:13 My land - That is, this land of Gilead, which was mine, but unjustly taken from me, by Sihon and Og, the kings of the Ammonites; and the injury perpetuated by Israel's detaining it from me. This land, before the conquests of Sihon and Og, belonged partly to the Ammonites, and partly to the Moabites. And indeed, Moab and Ammon did for the most part join their interests and their forces.