The Songhai Empire
Songhai, centred on Gao on the middle Niger, replaced Mali as the great power of West Africa under Sonni Ali and reached its height under Askia Muhammad.

David Sessoms · CC BY-SA 2.0 · Source
Songhai was a state centred on Gao on the middle Niger, at one time subject to Mali. Sonni Ali, who came to the throne in 1464, took Timbuktu in 1468 and then Djenné, supplanting Mali. His successor Askia Muhammad built an Islamic administration and army and made the pilgrimage to Mecca, and learning flourished at Timbuktu around the Sankore Mosque. Rich from the trans-Saharan trade, the empire fell in 1591 to a Moroccan army armed with muskets.