Judges 3:1-4

Now these are the nations which the LORD left [in order] to test Israel by them (that is, all [the people of Israel] who had not [previously] experienced any of the wars in Canaan; only in order that the generations of the sons of Israel might be taught war, at least those who had not experienced it previously). The remaining nations are: the five lords (governors) of the Philistines, all the Canaanites, the Sidonians, and the Hivites who lived on Mount Lebanon from Mount Baal-hermon to the entrance of Hamath. They were [allowed to remain] for the testing of Israel, to determine whether Israel would listen to and obey the commandments of the LORD, which He had commanded their fathers (ancestors) through Moses.