From George Ayittey:
The period 1880-1950 may be characterized as the golden age of peasant Prosperity in Africa. Though colonialism was invidious, one of its little-known and acknowledged “benefits” was the peace it brought Africa. The slave trade and competition over resources had fueled many of the tribal wars in precolonial Africa – just as competition over mineral resources, in particular diamonds, fueled wars in Angola, Congo, Liberia, and Sierra Leone in the twenty-first century. The slave trade generates intense emotional reaction among blacks. Unfortunately, however, there is much confusion and mythology about African participation in that abominable trade, which I have tried to clarify in an addendum at the end of this chapter.More here