From the Watchtower, January 1, 2010 (p. 13):
Why were the Canaanites displaced?
The Canaanites were, in a sense, squatters in a land that did not belong to them. How so? Some 400 years earlier, God had promised the faithful man Abraham that his descendants would possess the land of Canaan. (Genesis 15:18) God kept that promise when he caused the nation of Israel, which descended from Abraham, to occupy the region. Of course, some might protest that the Canaanites already lived there and therefore had a right to the land. But surely, as the Sovereign of the universe, God has the ultimate right to determine who will live where.-Acts 17:26; 1 Corinthians 10:26.