When the portuguese took over the kingdom they didn't want the swahili people to have any part in the african trade. The portuguese was not able to take control of the successful trading network, so around the late 16th century the Iman of oman took control of swahili coast, and dismissed the portuguese from any authority they had. The Iman of oman was still never able to create the wealthy and powerful trading network the swahili people once had. Swahili was never what it once was but in the 18th century it became a commercial trade
The Sayfawa dynasty was the mayor ruling dynasty through history. Kanem-Borno became very wealthy under Alooma reign. The sale of slaves was also an economic activity, and main export, including cotton, kola nuts, ivory, perfume and wax. Also, the Damara people of Namibia, who were considered nomadic people, were African mathematics, and they developed an advanced mathematical system. In ethiopia, they develop a system of calculation that function without fractions.
