2 King Sihon of the Amorites, who lived in Heshbon, was defeated. His kingdom included Aroer, on the edge of the Arnon Gorge, and extended from the middle of the Arnon Gorge to the Jabbok River, which serves as a border for the Ammonites. This territory included the southern half of the territory of Gilead.
Matthew Henry's Commentary on Joshua 12:2
Commentary on Joshua 12:1-6
(Read Joshua 12:1-6)
Fresh mercies must not drown the remembrance of former mercies, nor must the glory of the present instruments of good to the church diminish the just honour of those who went before them, since God is the same who wrought by both. Moses gave to one part of Israel a very rich and fruitful country, but it was on the outside of Jordan. Joshua gave to all Israel the holy land, within Jordan. So the law has given to some few of God's spiritual Israel worldly blessings, earnests of good things to come; but our Lord Jesus, the true Joshua, provided for all the children of promise spiritual blessings, and the heavenly Canaan.