> And if you go back far enough, it's also well known that the Bantu peoples were colonizers in their own right, and there still exist tensions between ethnic Bantus and indigenous peoples--e.g. pygmies.

It's not necessary to go back particularly far. The Bantu Expansion took place within the historical period. The ancient Egyptians wrote about (and painted) the African peoples of Kush to their south; those peoples are now extinct.

The Bantu reached South Africa at roughly the same time the Dutch did.