Portugal's Founding Role in the Transatlantic Slave Trade

Portugal is the European power most directly responsible for opening the transatlantic slave trade. In 1441, an expedition led by Nuno Tristão and Antão Gonçalves, sailing under the sponsorship of Prince Henry the Navigator, seized a small number of people, commonly cited as around ten, from the Rio de Oro coast of what is now Mauritania and brought them back to Portugal, the first recorded instance of sub-Saharan Africans being transported to Europe by sea for enslavement. The trade was rapidly institutionalized: by 1444 a larger expedition under Lançarote de Freitas returned to the port of Lagos with roughly 235 captive Africans, who were sold at what became Europe’s first slave market for the Atlantic trade. Prince Henry, who had backed the voyages chiefly to find a sea route around Muslim-controlled trans-Saharan trade networks and locate gold, quickly recognized the profitability of human trafficking as well, and Portugal secured a formal claim to exclusive trading rights along the West African coast from the Pope in the 1450s.

For roughly the next two centuries, Portuguese merchants dominated the European trade in enslaved Africans, operating first from coastal forts such as Elmina, built in 1482 in what is now Ghana, and later from bases in the Congo-Angola region. That dominance was never absolute: Spain, England, France, and the Netherlands all periodically challenged Portuguese trading rights, but it held its shape until the 1600s, when the political union of the Spanish and Portuguese crowns from 1580 to 1640 opened the door for Spain to grant direct slaving contracts, known as asientos, to Dutch merchants, who used them to break into the trade Portugal had treated as its own. English and French traders followed, and by the eighteenth century they, not the Portuguese, controlled the largest share of the transatlantic trade, even though Portuguese and Brazilian traders continued carrying more captive Africans across the Atlantic in absolute numbers than any other nation over the trade’s full multi-century span, most of them destined for Brazil.

Two further claims commonly attached to Portugal’s history deserve more careful treatment than they usually get. Portugal is often called the last European nation to abolish slavery, but that distinction actually belongs to Spain: Portugal declared slavery abolished throughout its territories by decree on February 25, 1869, with transitional labor obligations for freed people (“libertos”) ending by 1878, while Spain did not abolish slavery in Cuba, its major slaveholding colony, until October 1886, seventeen years later. Portugal was undeniably a late abolitionist by European standards, just not the very last. Portugal is also frequently described as the last European nation to free its African colonies, based on the Portuguese Colonial War, which ended in 1974-75 with the independence of Angola, Mozambique, Guinea-Bissau, Cape Verde, and São Tomé and Príncipe after a right-wing dictatorship collapsed in Lisbon’s 1974 Carnation Revolution. That, too, is close but not exact: France held onto Djibouti, its last African territory, until June 1977, two years after Portugal’s African empire dissolved. Portugal’s decolonization was nonetheless unusually late, sudden, and violent by comparison with Britain’s and France’s staggered withdrawals across the 1950s and 1960s, and it is fair to call Portugal one of the last, if not strictly the final, European power to relinquish African territory.