Islam slave trade

[Gawdzilla Sama]

All the slaves sold to Europeans on the West African coast were the prisoners of Africans.

Untrue.
Europeans (primarily the Portuguese, British, and Dutch) did conduct slave raids along the West African coast; Especially in the early phases of the of the TST.

The military-level missions led by Europeans did have some success, but again it was the Africans who enabled these.

In regards to the captives who were sold to slavers by African middlemen--Africans did not subscribe to  the notion of a homogeneous "African" or "Black" ethnicity--No reason why they would considering the sheer amount of ethnicity/genetic diversity among people living on the continent. That's a box Eurocentrists invented and tossed them all of them in.

Worth noting, when running with the "they sold themselves" narrative. For the most part, leaders and merchants were selling and trading captives/POWs they regarded as foreign; Not subjects of their own tribes/kingdoms.

The slave trade: the History of the Atlantic slave trade 1440-1870 by Hugh Thomas, is a good read on this.