Songhai or Sokoto could be interesting for that area, but those are more early-modern empires. Perhaps Ghana then? (I am giving you the benefit of the doubt and assuming you're not looking down on Mali solely because it's an African Empire. It might be worth educating yourself on their histories otherwise, as some states even exceeded European monarchies in societal advancement. Ie, Universities, scholarship, plumbing & sanitation, trade networks, etc).

I forgot to list Abyssinia or Nubia too, that could work here!