I would like to see too South-Africa in late came (could start from Zulu civilization). In late game Nigeria would be nice too. It has largest population and economy of Africa. It's trade and foreign policy has impact for other countries (including military interventions) that is why it could be civilization rather than independent. There have been empires in present day Nigeria almost three thousand years but how to make them in one civilization is quite tricky. And about colonization of Africa. Most of it was done in late 19th century. Before that of course there where trading posts and forts. Most of transatlantic slave trade was done with African kingdoms. West Africa was especially tricky to conquest because mosquitoes (with malaria) kills horses. Invention of machine gun helped colonial powers to conquer West Africa.