Because Amerindians died in large numbers, and insufficient numbers of Europeans were prepared to cross the Atlantic, the form that this demand took was shaped by conceptions of social identity on four continents, which ensured that the labor would comprise mainly slaves from Africa. But the central question of which peoples from Africa went to a given region of the Americas, and which group of Europeans or their descendants organized such a movement cannot be answered without an understanding of the wind and ocean currents of the North and South Atlantic. There are two systems of wind and ocean currents in the North and South Atlantic that follow the pattern of giant wheels - one lies north of the equator turns clockwise, while its counterpart to the south turns counterclockwise. .
The northern wheel largely shaped the north European slave trade and was dominated by the English. The southern wheel shaped the huge traffic to Brazil which for three centuries was almost the almost exclusive preserve of the largest slave traders of all, the Portuguese.(1) Despite their use of the Portuguese flag, slave traders using the southern wheel ran their business from ports in Brazil, not in Portugal. Winds and currents thus ensured two major slave trades the first rooted in Europe, the second in Brazil. Winds and currents also ensured that Africans carried to Brazil came overwhelmingly from Angola, with south-east Africa and the Bight of Benin playing smaller roles, and that Africans carried to North America, including the Caribbean, left from mainly West Africa, with the Bights of Biafra and Benin and the Gold Coast predominating. Just as Brazil overlapped on the northern system by drawing on the Bight of Benin, the English, French, and Dutch carried some slaves from northern Angola into the Caribbean.
African Agency and Resistance.
If demand for slave-grown produce, social identity, and the Atlantic environment were three key factors shaping the traffic, the agency of Africans comprised a fourth major influence, but one which has received less attention from historians.
