What states existed in Africa in the Middle Ages? When and why did the slave trade originate?

Ethiopia, Egypt, Tunisia, Morocco, Sudan and the island of Madagascar.
Began at the end of the 15th century. colonial conquests had a heavy impact on the life of African peoples. Traditional trade ties were disrupted, colonial wars led to the destruction of local industries, and sometimes to the death of entire states. The slave trade, which lasted until the middle of the 19th century, was called a bloody nightmare.

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