The early African people from the Sahara that ended up spreading to many different areas of Africa were the Bantu. With that, their culture and language was also spread around. They were a skillful people in their age. They were capable of agriculture with better tools thanks to their ironworking skills, which helped them promote extensive trade; since they could make superior agriculture tools and weapons with iron.
1993 because that when evrthing stared to happen
The answer is agriculture and trade warfare.