Final answer:
In the mid-fifteenth century, Portuguese explorers purchased enslaved people from Mali on the Senegambia coast to bypass the Muslim-controlled trade in gold and spices. Enslaved people traded on the Swahili coast mostly came from the interior of the African continent. The seventeenth-century slave trade expanded significantly on the Swahili coast and involved European traders.
Step-by-step explanation:
Mid-Fifteenth Century Slave Trade in Senegambia
In the mid-fifteenth century, the Portuguese explorers were the ones who purchased enslaved people from Mali on the Senegambia coast. They sought to bypass Muslim North Africans who had a monopoly on the sub-Saharan trade and realized that transporting slaves could be profitable. With the arrival of Europeans, such as the Portuguese, the nature of the slave trade in Africa was transformed, rerouting much commerce away from the trans-Saharan trade routes of the West African interior.
Origin of Enslaved People in the Swahili Coast Trade
The source of most of the enslaved people who were traded on the Swahili coast was the interior of the African continent. Bantu peoples were sold into slavery by merchants who had purchased them through African intermediaries, demonstrating that the demand for enslaved people in the Indian Ocean trade network was a driving factor in regional conflicts and warfare.
Seventeenth Century Slave Trade Expansion
By the seventeenth century, the slave trade on the Swahili coast had grown significantly with the influx of traders from Oman and the involvement of European slave traders like the Dutch and the Portuguese. This indicates the significance of the Indian Ocean as another major site for the slave trade alongside the established Atlantic trade.