It was so profitable that they sold to the Spanish
The Portuguese were so good at securing and transporting enslaved Africans that they were major suppliers to the Spanish. This was definitely a unique arrangement because other Europeans who traded in African slaves traveled to the source.
While there were legitimate slave traders recognized by the Portuguese crown who sold enslaved Africans to Spain, there were those who also sold “contraband slaves” to their Iberian neighbors.
Spain acquired over 500,000 enslaved Africans over 300 years, a significant percentage of whom were sold by Portugal.
