They used the hamatic hypothesis to justify this. And this was how they subdued the Africans with this religious reform.

They claimed that Jacob cursed the descendants of Ham to be hewers of wood and fetchers of water after Ham had seen his father's (Jacob) nakedness and called his brothers to laugh. They claimed that Ham and his descendants fled towards Africa and to some part of America... but how true is this?

They came to us with the Bible and the Plough.

And their claims were highly biased. Now this is what we have to face.