Slavery and the African Slave Trade

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Slavery and the African Slave Trade

Chattel slavery has been, and in some parts of the world remains even today, a common feature of human societies. A conservative estimate suggests that perhaps 27 million people still live under some form of slavery in the early twenty-first century, with perhaps two-thirds of them being bonded labor in the Indian subcontinent (Bales 2000, pp. 8–9). Historically, most forms of slavery have been racially unbounded, but in the century after Columbus landed in the Americas there emerged one of the most brutal, highly racial systems of slavery known to history. Underpinned by the deportation of 11 million or more enslaved Africans, transatlantic chattel slavery rested on history's largest and most concentrated coerced oceanic movement of people. Largely relocated to tropical and subtropical regions where they produced crops, precious metals, or other goods for export to Europe, chattel slaves nevertheless came to be found throughout the Americas. For the most part, their numbers failed to increase naturally—the main exception being the British North American mainland colonies that became the United States. Most American slave-owning societies, therefore, relied on continuing arrivals of new slaves from Africa to sustain and expand their labor force. As the total slave population of the Americas grew, increasing proportions of the slaves taken from Africa became replacements for those who died prematurely. Without slave imports the growth of slavery in the Americas and the concomitant massive rise of transatlantic and intra-American trades in slave-produced commodities would have been much slower than it actually was. It was unsurprising, then, that eighteenth-century political economists such as Malachy Postlethwayt saw the slave trade as the pillar upon which Atlantic commerce rested during the Age of Mercantilism. Because such trades were among the most dynamic elements of the overseas commerce of Western European nations at the time, it is equally unsurprising that the relationship between the enslavement of Africans and eighteenth-century capitalist development in the West has become a major area of historical debate, feeding demands for reparations for the descendants of the millions of Africans deported to the Americas.


From the fifteenth to nineteenth centuries Europeans established numerous slave "factories" on Africa's west coast which were used as holding areas or warehouses where slaves were imprisoned until shipped overseas in the infamous "middle passage." Often surrounded by defensive walls, the factories were also known as "castles." One slave castle (now a UNESCO world heritage monument) was established by the Dutch in 1776 at Goree Island, off the coast of Senegal. The prolific British slavers also maintained their own factories; their post on Sierra Leone's Bance Island was heavily defended against both enemy attack and slave uprisings. Though small, Bance Island had an extensive infrastructure, including a stone jetty, European quarters, and Africa's only golf course. Even with such comforts, the annual death rate for Europeans on Bance Island was almost 50 percent. For the slaves, chained in overcrowded, disease-ridden holding cells, and separated from loved ones, conditions were much more horrific. As the last stop for slaves bound for the Americas, both Goree and Bance Islands had "doors of no return" through which millions of Africans permanently departed their home-lands and lives as free persons.

David J. Clarke


Like Columbus's voyages, transatlantic slavery and the slave trade that nurtured it originated in the Mediterranean. From ancient Egyptian times onwards, civilizations bordering the Mediterranean often had slave foundations. Slavery underpinned the fifteenth-century Ottoman Empire. It existed simultaneously in Venice, southern France, the Iberian Peninsula, Morocco, and the islands of the "inland sea." Slaves were employed as soldiers and as oarsmen in the naval galleys of Mediterranean states. They worked in households, in craft manufacture, and in agriculture. The last included sugar cultivation, which, though seen as "a marginal operation at best" in the Mediterranean (Schwartz 2004, p. 27), spread from east to west during the medieval period, and by the late fifteenth century was established in Madeira and the Canaries. From there it migrated to Fernando Po and São Tomé in the Gulf of Guinea before being transplanted to northeast Brazil by the 1530s. Whether in sugar production or other activities, Africans commonly constituted an important part of the coerced labor force of the Mediterranean world before and after 1500, but they soon became the predominant, if not almost exclusive, form of enslaved labor in the Atlantic islands and early colonial Brazil. By the end of the sixteenth century, too, they worked alongside native Indians in the extractive industries of Spanish America. In short, slavery assumed an increasingly African face as it extended from the Mediterranean to the "New World" after 1500.

Slavery and export slave trades existed in Africa before European fifteenth-century contact with the Gulf of Guinea by sea. Slave exports to the Mediterranean and the Middle East via the Sahara and Indian Ocean and Red Sea ports long predated the Atlantic slave trade. Though smaller in scale in 1500 to 1850 than their Atlantic counterpart, they probably grew even as the latter grew, peaking perhaps in the nineteenth century. Because Africans born into slavery were apparently only rarely deported, it is likely that the growth of export slave trades after 1500 ensured that the sum total of Africans taken captive rose, with the transatlantic traffic foremost among its causes. Debate surrounds the methods by which Africans shipped to the Americas and elsewhere were initially enslaved. Most deportees were probably victims of warfare or violence by states, warlords, or traders. Some, however, were condemned through judicial process into slavery, and some others sold themselves or were sold into slavery to escape starvation. The last may have been particularly evident in drought-prone regions such as upper Guinea and Angola. In the long run, however, there seems to have been only a tenuous correlation between the capacity of most African regions to supply slaves for export, ecological conditions, and local population densities. More critical than ecology and demography in influencing patterns of slave exports were sociopolitical conditions that helped to shape interregional differences in the efficiency of slave-supply mechanisms and levels of resistance of the trade's victims to capture. Such factors were sufficiently powerful to allow certain slave-supply regions in Africa to more than offset disadvantages in terms of proximity to Europe or America or to transatlantic wind and current systems, and to become among the principal suppliers of slaves to the Americas. Historians now attribute much greater weight to African agency (or factors internal to Africa) in determining regional patterns of slave exports from Africa than was once the case. They also recognize that a transatlantic traffic in enslaved Africans that at its height involved up to 50,000 or more victims a year rested on the establishment of sustainable and stable economic relations between African suppliers and external shippers of slaves. In this respect at least, the export slave trade from Africa to the Americas was not fundamentally different from most other contemporary trades. By retaining control over supply, African dealers often were able to dictate the terms upon which slaves were sold into exile, especially when, as in the eighteenth century, external demand for slaves rose substantially.


The Portuguese were the first regularly to ship enslaved Africans across the Atlantic, having previously pioneered exploration of Atlantic Africa by sea and developed a sea-borne traffic in African commodities and slaves to Lisbon and the Atlantic islands. They retained a near monopoly of the Atlantic slave trade during the sixteenth century, supplying Brazil's growing labor needs and, through tenure of the asiento (permission to trade), those of the silver- and gold-producing parts of Spanish Americas. In the 1630s, however, the Dutch challenged Portugal's stranglehold on slave trafficking, seizing control in 1629 to 1636 of Portuguese territories in northeast Brazil and in 1637 to 1641 of their ports of Elmina and Luanda in Africa. Such actions laid a platform for a permanent involvement in the Atlantic slave trade by the Dutch, but Portugal's early recapture of its Brazilian colonies and Luanda probably prevented them from usurping Portugal's supremacy in slave trafficking.

That dubious distinction fell instead to the English, who, on the back of surging demand for slaves within their own Caribbean colonies after 1645 and rigorous enforcement of trade monopolies with the same, had forged by 1670 an entry into the African trade sufficiently large to enable them to go on and dominate the international slave trade during the following 140 years. Indeed, between 1670 and 1807, at which date Parliament outlawed transatlantic slave-carrying by British subjects, the British carried almost as many slaves across the Atlantic as all other carriers combined—Portuguese, Dutch, French, Danish, and, after 1776, U.S. citizens. British dominance, moreover, almost certainly would have continued but for Parliamentary interdiction, which allowed others to fill the void. The most prominent were Portuguese-Brazilian and Spanish-Cuban carriers, whose expanded presence prompted a post-1807 shift in the overall pattern of departures of slave ships from Europe to the Americas, and ensured that Portuguese-speakers asserted a level of influence over the slave trade not seen since before 1650. The first to enter and among the last to quit transatlantic slave trafficking, the Portuguese were, largely courtesy of British abolition in 1807, the largest single shippers of African slaves to America, accounting for perhaps 5 million, or some 45 percent of the 11 million shipped from 1500 to 1867. Second overall were the British, who, despite entering the trade relatively late and being denied involvement after 1807, still accounted for about 30 percent, or some 3.25 million slaves. Together, therefore, Portuguese- and English-speakers were responsible for about three-quarters of all Africans entering the Atlantic slave trade. Of the remaining 2.75 million captives, some 1.5 million left Africa in French ships, and a further 1 million, more or less equally divided, in ships owned by either Dutch- or Spanish-speakers. Carriers based in the United States and Denmark accounted for the vast majority of the remaining quarter-million slaves.

The intensity of participation in slave trading of different carriers varied through time, but the widening international participation in the trade ensured a sustained and dramatic rise in the trade's scale between the early seventeenth century and the onset of abolitionism nearly two centuries later. Probably less than 1 million Africans entered the Atlantic slave trade before 1640; during the following century and a half it appears that some 6.8 million did so. The entry of the Dutch, the British, and, by 1700, the French into the slave trade thus prompted a long-term surge in activity, with annual shipments of slaves at the trade's peak in 1763 to 1793 being up to seven times higher than when the Dutch seized Portuguese territories in Brazil and Africa in 1636 to 1641. After 1790 abolitionism combined with slave rebellion in the principal French slave colony of Saint-Domingue in 1791 and the outbreak of war in Europe in 1793 to lower levels of activity through 1815, but the return of peace after Waterloo and continuing demand for slaves in the non-British Caribbean and Brazil encouraged a resurgence in transatlantic slave trafficking, even in the face of British efforts to suppress the activity. Indeed, between 1815 and 1850, when a British blockade brought the Brazilian slave import trade to a close, transatlantic slave trafficking remained at historically high levels, with close to 3 million slaves being deported from Africa in these years. Only after 1850 did the Atlantic slave trade contract sharply, the speed of its collapse contrasting dramatically with the measured pace of its expansion before 1600.

Enslaved Africans were mostly employed in the Americas in tasks related to the commercial exploitation of land resources and the marketing of the commodities produced in external markets, principally in Europe. From the sixteenth century onwards, enslaved Africans worked in Spanish American mines, producing the silver that helped to fuel inflation in Europe between 1540 and 1640. By the eighteenth century African slaves also labored in the gold mines of Mineas Gerais of Brazil, the output from which found its way through Lisbon to other parts of Europe, notably London. By this time, enslaved Africans were employed in producing tobacco in Maryland and Virginia, rice in South Carolina, and cotton, spices, dyestuffs, and coffee in the British and French West Indies. By the early nineteenth century, production of cotton and coffee by enslaved Africans spread to the United States, Cuba, and Brazil. But as long as entry into slave trading remained unfettered by law, it was the production of sugar—initially in northeast Brazil, later, after 1645, in the British, Dutch, and French West Indies, and finally, after 1790, in Cuba and southeast Brazil—that largely dictated both the rhythm of growth of transatlantic slave trafficking and the geographical patterns of slave arrivals in the Americas between and within European colonial jurisdictions. Produced largely to satisfy the "sweet tooth" of European consumers, sugar was, in turn, an insatiable consumer of African slaves, the vigorous labor regimes associated with its production being an important factor in determining the failure of Africans slaves to reproduce in most American plantation economies. It also dictated the scale and shifting distribution of slave arrivals across and within national jurisdictions within the Americas. Thus, Barbados and Martinique dominated arrivals in the British and French West Indies, respectively, before 1700, and Jamaica and Saint-Domingue did so in the following century. Thereafter, it was sugar cultivation in Cuba and its extension from northeastern and southeastern Brazil that largely dictated the contours of slave trading through 1850. This sequential spread of sugar cultivation across political jurisdictions in the Americas explains shifts over time in national shares of the slave trade, as most carriers tended to land their human cargo at places under their political control. It ensured, too, that Brazil, which pioneered American sugar cultivation and persisted in the industry through to the end of slave trafficking, took two out of every five slaves shipped from Africa between 1500 and 1867, and that the British, Dutch, French, and, after 1790, the Spanish West Indies received the great majority of the rest. Sugar and slavery were, in short, inseparable companions: the lives of three out of every four enslaved Africans landing in the Americas were shaped by sugar production.

Satisfying sugar's insatiable demand for enslaved labor placed pressures at times on African slave supply, prompting rises in slave prices in Africa and movements in the terms of trade in favor of suppliers, and encouraging the opening up of new sources of slaves. Eight regions in Africa are conventionally seen to have supplied slaves to the Americas: from north to south these were Sene-gambia, Sierra Leone, the Windward Coast, the Gold Coast, the Slave Coast (or Bight of Benin), the Bight of Biafra, Angola (or West-Central Africa), and southeast Africa. Among these regions, Angola was the largest and most persistent source of slaves, the wind and current systems of the South Atlantic favoring close links with Brazil, the most enduring market for slaves in the Americas. Overall, some 4.9 million (or two out of every five) of the slaves entering the Atlantic slave trade originated in Angola. Outside of Angola, the Slave Coast, the Bight of Biafra, and the Gold Coast were, in that order, the next three principal suppliers of slaves to the Americas, each contributing over 1 million and collectively accounting for nearly 4.6 million deportees.

The vast majority were taken away by British, Dutch, and French shippers and landed in their West Indian colonies before 1807, though the Portuguese to northeast Brazil shipped large proportions of those from the slave coast before and after this date. Relative to these four principal sources, slave shipments from other regions exhibited much greater variability through time, usually being modest in scale but rising to substantial heights after 1750 at Senegambia, Sierra Leone, and the Wind-ward Coast, and, after 1800, at southeast Africa. The lateness with which these last four regions entered the Atlantic slave trade probably reflected higher costs of slave procurement compared to other regions, reinforced in the case of southeast Africa by its extreme remoteness from American slave markets.


Slaves boarding ship at certain ports or regions in Africa had a higher risk of dying in the voyage to America than those boarding elsewhere. This was especially true of slaves from the Bight of Biafra and from southeast Africa. Wherever slaves boarded ship, however, mortality in general, and age-specific mortality in particular, was very high in the so-called "middle passage," or Atlantic crossing. Most shiploads of slaves comprised captives in the prime years of life, yet before 1700 as many as 25 percent of those embarked in Africa typically died before reaching the Americas.

Thereafter, a combination of developments in disease prevention and public health, economic incentives, and greater experience on the part of shippers helped to reduce mortality levels, but they still averaged 10 to 15 percent in the late eighteenth century, and may even have risen again in the age of abolitionism. Such wastage of human life was, of course, only one part of the high social costs of slave trafficking, which, when allowance is made for deaths in the course of enslavement and marketing of slaves within Africa and in the "seasoning" period after arrival in the Americas, meant that the Atlantic slave trade was one of the greatest tragedies in history.

Increasing awareness of this fact—astutely exploited in propaganda terms by a growing band of abolitionists in Britain and elsewhere from the 1780s onwards—proved to be a critical factor in prompting political, diplomatic, financial and naval intervention to regulate, outlaw, or ultimately suppress slave trafficking between Africa and the Americas in the following seventy years. Measures by Britain and the United States in 1807 to 1808 to end slave carrying by their nationals were followed after 1815 by moves to pressure or bribe other participants in Europe and Africa to end their involvement, and culminated in a British naval blockade of Brazilian slave-importing ports in 1850.

Such interventions in the pursuit of humanitarianism imposed significant costs directly and indirectly on the taxpayers and consumers of Britain, and are often considered as integral to broader economic, social, and ideological changes in Britain and elsewhere during the Age of Industrialization. Two centuries after the passing of legislation by the British and U.S. governments to end their slave trades in 1807 to 1808, debate continues to rage over the relative contributions of economic and other factors in motivating abolitionism. But one thing seems clear: if ending the Atlantic slave trade entailed costs, they were ones that in 1815 to 1850 Britain, the world's wealthiest and most powerful nation, whatever the motives behind its policy, was both willing and able to accept.

SEE ALSO Agriculture; Angola; Bahia; Brazil; Charleston; Coffee; Cotton; Empire, British; Empire, Portuguese; Jamaica; Laborers, Coerced; Labor, Types of; Liverpool; London; Nantes; Population—Emigration and Immigration; Sugar, Molasses, and Rum.


Bales, Kevin. Disposable People: New Slavery in the Global Economy. Berkeley: University of California Press, 2000.

Curtin, Philip D. The Atlantic Slave Trade: A Census. Madison: University of Wisconsin Press, 1969.

Eltis, David. Economic Growth and the Ending of the Transatlantic Slave Trade. Oxford, U.K.: Oxford University Press, 1987.

Eltis, David. The Rise of African Slavery in the Americas. Cambridge, U.K.: Cambridge University Press, 2000.

Eltis, David, and Morgan, Philip D., eds. New Perspectives on the Transatlantic Slave Trade, special edition of William and Mary Quarterly 58, no. 1 (January 2001).

Eltis, David; Lewis, Frank D.; and Sokoloff, Kenneth L.; eds. Slavery in the Development of the Americas. Cambridge, New York: Cambridge University Press, 2004.

Fogel, Robert W. Without Consent or Contract: The Rise and Fall of African Slavery in the Americas. New York: Norton, 1989.

Inikori, Joseph E. Africans and the Industrial Revolution in England. Cambridge, U.K.: Cambridge University Press, 2002.

Klein, Herbert S. The Atlantic Slave Trade. Cambridge, U.K.: Cambridge University Press, 1999.

Lovejoy, Paul E. Transformations in Slavery, 2nd edition. Cambridge, U.K.: Cambridge University Press, 2000.

Postma, Johannes M. The Atlantic Slave Trade. Westport, CT: Greenwood Press, 2003.

Schwartz, Stuart B., ed. Tropical Babylons: Sugar and the Making of the Atlantic World. Chapel Hill: University of North Carolina Press, 2004.

Solow, Barbara L., ed. Slavery and the Rise of the Atlantic System. Cambridge, New York: Cambridge University Press, 1991.

Thornton, John K. Africa and Africans in the Making of the Atlantic World, 2nd edition. Cambridge, U.K.: Cambridge University Press, 1998.

Williams, Eric. Capitalism and Slavery. [1944]. Chapel Hill: University of North Carolina Press, 1994.

David Richardson

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