In little more than a century, from roughly 1780 to 1890, a remarkable transformation occurred in human affairs as slavery, widely practiced and little condemned since at least the beginning of civilization, lost its legitimacy and was largely ended. In this amazing process, the ideas and practices of the Atlantic revolutions played an important role.

Enlightenment thinkers in eighteenth-century Europe had become increasingly critical of slavery as a violation of the natural rights of every person, and the public pronouncements of the American and French revolutions about liberty and equality likewise focused attention on this obvious breach of those principles. To this secular antislavery thinking was added an increasingly vociferous religious voice, expressed first by Quakers and then by Protestant evangelicals in Britain and the United States. To them, slavery was “repugnant to our religion” and a “crime in the sight of God.”18 What made these moral arguments more widely acceptable was the growing belief that, contrary to much earlier thinking, slavery was not essential for economic progress. After all, England and New England were among the most prosperous regions of the Western world in the early nineteenth century, and both were based on free labor. Slavery in this view was out of date, unnecessary in the new era of industrial technology and capitalism. Thus moral virtue and economic success were joined. It was an attractive argument. The actions of slaves themselves likewise hastened the end of slavery. The dramatically successful Haitian Revolution was followed by three major rebellions in the British West Indies, all of which were harshly crushed, in the early nineteenth century. The Great Jamaica Revolt of 1831–1832 was particularly important in prompting Britain to abolish slavery throughout its empire in 1833. These revolts demonstrated clearly that slaves were hardly “contented,” and the brutality with which they were suppressed appalled British public opinion. Growing numbers of the British public came to believe that slavery was “not only morally wrong and economically inefficient, but also politically unwise.”19

These various strands of thinking—secular, religious, economic, and political—came together in abolitionist movements, most powerfully in Britain, which brought growing pressure on governments to close down the trade in slaves and then to ban slavery itself. In the late eighteenth century, such a movement gained wide support among middle- and working-class people in Britain. Its techniques included pamphlets with heartrending descriptions of slavery, numerous petitions to Parliament, lawsuits, and boycotts of slave-produced sugar. Frequent public meetings dramatically featured the testimony of Africans who had experienced the horrors of slavery firsthand. In 1807, Britain forbade the sale of slaves within its empire and in 1834 emancipated those who remained enslaved. Over the next half century, other nations followed suit, responding to growing international pressure, particularly from Britain, then the world’s leading economic and military power. British naval vessels patrolled the Atlantic, intercepted illegal slave ships, and freed their human cargoes in a small West African settlement called Freetown, in present-day Sierra Leone. Following their independence, most Latin American countries abolished slavery by the 1850s. Brazil, in 1888, was the last to do so, bringing more than four centuries of Atlantic slavery to an end. A roughly similar set of conditions—fear of rebellion, economic inefficiency, and moral concerns—persuaded the Russian tsar (zahr) to free the many serfs of that huge country in 1861, although there it occurred by fiat from above rather than from growing public pressure.

None of this happened easily. Slave economies continued to flourish well into the nineteenth century, and plantation owners vigorously resisted the onslaught of abolitionists. So did slave traders, both European and African, who together shipped millions of additional captives, mostly to Cuba and Brazil, long after the trade had been declared illegal. Osei Bonsu, the powerful king of the West African state of Asante, was puzzled as to why the British would no longer buy his slaves. “If they think it bad now,” he asked a local British representative in 1820, “why did they think it good before?”21 Nowhere was the persistence of slavery more evident and resistance to abolition more intense than in the southern states of the United States. It was the only slaveholding society in which the end of slavery occurred through such a bitter, prolonged, and highly destructive civil war (1861–1865).

The end of Atlantic slavery during the nineteenth century surely marked a major and quite rapid turn in the world’s social history and in the moral thinking of humankind. Nonetheless, the outcomes of that process were often surprising and far from the expectations of abolitionists or the newly freed slaves. In most cases, the economic lives of the former slaves did not improve dramatically. Nowhere in the Atlantic world, except Haiti, did a redistribution of land follow the end of slavery. But freedmen everywhere desperately sought economic autonomy on their own land, and in parts of the Caribbean such as Jamaica, where unoccupied land was available, independent peasant agriculture proved possible for some. Elsewhere, as in the southern United States, various forms of legally free but highly dependent labor, such as sharecropping, emerged to replace slavery and to provide low-paid and often-indebted workers for planters. The understandable reluctance of former slaves to continue working in plantation agriculture created labor shortages and set in motion a huge new wave of global migration. Large numbers of indentured servants from India and China were imported into the Caribbean, Peru, South Africa, Hawaii, Malaya, and elsewhere to work in mines, on plantations, and in construction projects. There they often toiled in conditions not far removed from slavery itself.

Newly freed people did not achieve anything close to political equality, except in Haiti. White planters, farmers, and mine owners retained local authority in the Caribbean, where colonial rule persisted until well into the twentieth century. In the southern United States, a brief period of “radical reconstruction,” during which newly freed blacks did enjoy full political rights and some power, was followed by harsh segregation laws, denial of voting rights, a wave of lynching, and a virulent racism that lasted well into the twentieth century. For most former slaves, emancipation usually meant “nothing but freedom.”22 Unlike the situation in the Americas, the end of serfdom in Russia transferred to the peasants a considerable portion of the nobles’ land, but the need to pay for this land with “redemption dues” and the rapid growth of Russia’s rural population ensured that most peasants remained impoverished and politically volatile.

In both West and East Africa, the closing of the external slave trade decreased the price of slaves and increased their use within African societies to produce the export crops that the world economy now sought. Thus, as Europeans imposed colonial rule on Africa in the late nineteenth century, one of their justifications for doing so was the need to emancipate enslaved Africans. The fact that Europeans proclaimed the need to end slavery in a continent from which they had extracted slaves for more than four centuries was surely among the more ironic outcomes of the abolitionist process.

In the Islamic world, where slavery had long been practiced and elaborately regulated, the freeing of slaves, though not required, was strongly recommended as a mark of piety. Some nineteenth-century Muslim authorities opposed slavery altogether on the grounds that it violated the Quran’s ideals of freedom and equality. But unlike Europe and North America, the Islamic world generated no popular grassroots antislavery movements. There slavery was outlawed gradually only in the twentieth century under the pressure of international opinion.