African civilizations that survived the slave trade were completely destroyed by colonization. The resistance to colonial invasion was absolutely heroic. Our ancestors, knowing that they were going to die, were litterally throwing themselves on the gunnery to prevent the advance of Europeans, and were exploded into pieces. Entire villages were razed and only a few people survived in some cases.
Image: Ruins of the Ashanti civilization (Ghana) on the left, Danhome civilization (current Benin) on the right