Gaeilge said:
Mansa Musa, a West African, was the richest person in history.
His wealth was achieved through slave trade.
Bingo, a guy so rich he brought 13,000 slaves with him for his pilgrimage to mecca (because of course he was moslem). And, again of course, he is going to be glorified in an upcoming hollywood film as a swell guy.
The Portuguese worked a lot on the trade from west Africa,
also enriching many kings in the process over centuries (though as the slave demand escalated in Brazil they had to forage/trade for slaves further and further inland.)
But overall the arab moslem slave trade has lasted (and continues to last) much longer than the European one, at much greater scale. If anyone should pay any Africans reparations as such, it should probably be the wealthy arab nation states. Spoiler; that's not gonna happen.