Atlantic slave trade

The Atlantic slave trade was the forced shipping of about 12.5 million Africans across the ocean to the Americas between the 1520s and the 1860s, the largest forced migration in history. Some 10.7 million survived the crossing; the rest died at sea. The ships were Portuguese, British, Spanish, French, Dutch, American and Danish, roughly in that order of volume, and most of the captives came from West and West-Central Africa, from Senegal down to Angola. They were sold on the African coast by African and Afro-European traders, usually as prisoners of war or as the proceeds of raids, in exchange for cloth, guns, iron, rum and cowrie shells.

It began because the Europeans who had conquered the Americas needed workers. The native population was collapsing from European diseases, and few Europeans would emigrate to cut cane. The Portuguese had already used African slaves on the sugar islands off Africa, and in 1518 the Spanish crown licensed shipments straight from Africa to its colonies; the first such voyages, from the Cape Verde Islands and São Tomé to Hispaniola, Puerto Rico and Cuba, sailed in the mid-1520s. Sugar in Brazil and the Caribbean drove the trade for three centuries; tobacco, rice, coffee, gold mines and, in the nineteenth century, cotton added to it. Brazil took the most people of all, almost half; the British Caribbean and Spanish America most of the rest. Only about 388,000 were landed in what is now the United States.

The crossing, the Middle Passage, took one to three months. People were chained below decks in spaces too low to sit up in, as the famous 1788 diagram of the Liverpool ship Brookes showed to the British public: 454 bodies drawn into its hold. Dysentery, smallpox and despair killed about one in seven on the way. On the Zong in 1781 the crew threw more than 130 living people into the sea and the owners claimed them on insurance; the case helped turn British opinion. Resistance was constant, on the ships and on the plantations, and in 1791 the enslaved people of Saint-Domingue rose and made Haiti the first free Black republic.

The trade peaked in the 1780s, when about 80,000 people a year were carried across, and was abolished while it was still enormously profitable. Quaker and evangelical campaigners in Britain, Josiah Wedgwood's medallion asking "Am I not a man and a brother?", Olaudah Equiano's memoir and petitions signed by hundreds of thousands brought Parliament to ban British ships from the trade in 1807; the United States banned imports from 1808. A quarter of all the people ever shipped were still carried after 1807, mostly to Cuba and Brazil, until British and finally American naval patrols closed the sea lanes; the last known voyage reached Cuba in 1867. Slavery itself outlived the trade: ended in the British colonies in 1833 to 1838, in the United States in 1865, in Cuba in 1886 and in Brazil in 1888.

Its legacy is the African diaspora of the Americas, tens of millions of people from Bahia to Harlem whose ancestors were carried in these ships, and the cultures, music and religions they made. It is also the wealth of the ports that organised it, Liverpool, Nantes, Lisbon, Rio de Janeiro and Charleston, the depopulation and wars it fed in Africa, and the racial ideas invented to justify it, which outlived it by a long way. The forts on the Gold Coast, the House of Slaves on Gorée and the Valongo Wharf in Rio are World Heritage sites, kept as places of memory.