Joshua 17:12, 16-18

But the sons of Manasseh were not able to [drive out the inhabitants and] take possession of these cities, because the Canaanites persisted in living in that land.

The sons of Joseph said, “The hill country is not enough for us, and all the Canaanites who live in the valley have iron chariots, both those who are in Beth-shean and its towns and those in the Valley of Jezreel.” Joshua said to the house of Joseph, to Ephraim and to Manasseh, “You are a numerous people and have great power; you shall not have only one lot, but the hill country shall be yours. For though it is a forest, you shall clear it and possess it to its farthest borders; for you shall drive out the Canaanites, even though they have iron chariots and though they are strong.”