The slavery thing. Not always as it seems. My wife and my "ex" before are Nigerian, both from Benin City.
Born and bred. Speak Edo their mother tongue, English and French.
Ruled since 1000 AD by the Oba(s) of Benin. World's longest same family of hereditary monarchs apparently.
Anyway. Big slavers were the Oba(s) of Benin.
Dealt with the Portuguese and after them the Dutch and then the British. And before any of them with other Kingdoms in Africa and the Arabs.
Last sovereign ruler in Africa until deposed by us Brits in 1896. The restored by us Brits in 1914.
But I always remember my "ex" in Paris. She was in her mid to late twenties then. Small but perfectly formed and all that.
We were at the Eiffel Tower. A group of load African Americans arrived. Noisy. Jostling. One of them shoved her.
Not good! She turned, looked at them, made her assessment and shouted.
"Look at these people. They do not know how to behave. For they are all, all of them, slaves and the descendants of slaves."
They were all struck silent. So the slavery thing, TB, not quite always how today's books would have it.
The traditional rulers of West Africa traded long before the "Brits" arrived, or the Europeans, in many things. Metal, palm oil, gems. And slaves.