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Slavery – the ownership and control of one human being by another, to the point of total obedience – is one of the grimmest phenomena of history, and sadly has been present in many times and places across the globe. People from all ethnic groups have been slaves, and slave masters.
But today in the West, the main historical example of slavery that comes to mind is the Atlantic trade in black slaves between the sixteenth and nineteenth centuries. The abiding image is of the slave ships, carrying Africans across the Atlantic in packed and utterly inhumane conditions, on a journey that all too many did not survive. How did this trade develop? What part did Britain play in it? And what factors brought it to an end?
The Rise of the Atlantic Slave Trade
An Atlantic trade in African slaves began in 1444, when the Portuguese began to ship slaves from West Africa to Europe. For the next hundred years, the main markets for these slaves were in Europe and the Atlantic islands owned by Portugal and Spain. However, the discovery of the Americas in 1492 led to the creation of new colonies with a great need for cheap labour, and from the mid-sixteenth century European ships were carrying African slaves to Brazil, the Caribbean, and North America, in steadily increasing quantities.
At first the Portuguese and the Spanish were the main organisers of the trade, but by the second half of the seventeenth century the countries of north-west Europe were becoming involved. During the eighteenth century, Britain was the foremost slave-trading power, alongside the French, the Dutch, the Portuguese, and the Spanish, all of whom had colonies in the New World.
A "triangular trade" operated, whereby ships carried European manufactures to Africa and exchanged them for slaves, who were then taken to the Americas, where they were traded for sugar, molasses, cotton, tobacco, indigo and other goods, which were brought back to Europe. It is estimated that, between the sixteenth and nineteenth centuries, over twelve million Africans were transported across the Atlantic, most of whom came from West Africa.
At each stage in the slaves' journey from Africa to the Americas, they faced great dangers and possible death. The first stage was the capture of people on the African mainland, and their movement to the coast. This was organised by local African potentates. European traders tended not to venture within Africa at this time because of the unsolved threat from disease, and waited instead at coastal trading stations for their cargo. African rulers had been engaged in slavery for many centuries already, capturing slaves for their own use or for sale to the Middle East; but the Atlantic trade marked a profound expansion of African slave dealings.
Those slaves who survived capture and the journey to the coast would then face the Atlantic crossing, which was every bit as terrible as popular memory would have it, although some attempts were made to improve conditions during the closing years of the trade. Mainly through dehydration, between ten and twenty-five per cent of the slaves would die routinely before the end of the voyage.
Having reached the Americas, those who survived the crossing faced a life of slavery on colonial plantations. Here, they were denied their freedom and dignity, and were treated with considerable brutality by their masters. Attempts by slaves to run away, and on occasion to revolt, were signs of their continued suffering. Many died within a few years in the plantations because of disease, with Brazil having an especially tragic record of high mortality. The deaths of slaves in the Americas, and the low birth rate of slave communities, meant that a continual influx of new slaves from Africa was demanded by the plantation owners.
Britain did not create the Atlantic slave trade, but there is no denying that it was heavily involved with the trade at its height during the eighteenth century. In these years, well over one-and-a-half million slaves were carried to the British Caribbean and to British North America, out of a total of over six million captives brought to the Americas as a whole. The ports of Bristol, Liverpool and London drew great wealth from the trade, and the British public benefited from large quantities of cheap slave-produced imports.
The Decline of the Slave Trade
In spite of this, during the nineteenth century, Britain was to play a leading role in the abolition of the slave trade. Its Parliament passed laws to abolish the trade in 1807 and to stop the use of slaves in British territories in 1833, though it granted slave-owners twenty million pounds in compensation for the latter (equivalent to over £1,000 million pounds today). Britain stood out for its strict enforcement of the abolition (creating a permanent naval patrol off the West African coast to act against slave ships), and for its repeated diplomatic efforts to encourage the other major slave-trading powers to follow suit.
France took action to stop its slave trade in 1815. Portugal and Spain continued to export Africans on a large scale to Brazil and Cuba until the mid-nineteenth century, but when this was brought to a halt, the Atlantic slave trade was effectively at an end.
Seen in the context of the Atlantic trade's long existence, its abolition was a remarkable change, and the question arises of how this came to happen. Above all, what factors converted Britain to such vehement anti-slavery? The obvious starting-point is the campaigns of Granville Sharp, Thomas Clarkson, William Wilberforce and their fellow evangelical Christians from the 1780s onwards. At the level of parliamentary politics, Wilberforce was the spearhead of anti-slavery for several years, and it would be wrong to belittle his contribution.
But this was not by any means the whole story of anti-slavery. Of vital importance was the large popular protest movement against slavery that emerged across Britain between the 1780s and 1830s, which created a series of petitions that contained hundreds of thousands of signatures. The sustained pressure from this movement had a lasting impact on the political elite, and made it impossible for the issue to be easily dismissed.
What was the basis of this movement? It reflected a new wave of popular ideas, especially a re-interpretation of the Christian duty towards the oppressed, as well as a conviction that restricting the freedom of labour was at odds with economic success. Such a wave of ideas was, in turn, enabled by the emergence of a national "public opinion", via the growth of newspapers and other types of printed matter, and relatively high levels of literacy. Anti-slavery was striking for the way in which, before modern electronic communications, a mass audience became rapt in events in other parts of the world.
Another crucial factor was the struggle of black people to gain their own liberation. In England, activists such as Olaudah Equiano and Ottobah Cugoano campaigned against slavery, as part of a community of freed black people in London that already numbered in the tens of thousands. Meanwhile in the Caribbean there was a long history of slave uprisings. This culminated in 1831-2 with the Sam Sharpe rebellion in Jamaica, reports of which had a direct impact on Parliament's decision to end colonial slavery.
For historians, the most controversial issue regarding the demise of the slave trade has been the degree to which economic change itself played a part. It has been asked, were the British slave plantations of the West Indies already in economic decline before the slave trade and slavery were abolished, and also was the nature of economic development within Britain making the home country less dependent on this area of trade? In addition, if the slave colonies were becoming less important for the home economy, did this have a discernable effect on politics in Britain, dampening opposition to anti-slavery?
Historians are far from reaching a consensus on these matters, with some describing the abolition of the slave trade and slavery as complementary with economic trends, while others see it as "econocide", i.e. as a moral or political act that flew in the face of economic interests.
The end of the Atlantic slave trade was not the end of slavery itself. In the Americas slavery was outlawed finally by all the major states by late 1880s (with Brazil being the last to act in 1888), but it continued in North Africa, the Middle East, and the Indian Ocean up to the 1900s, and persisted in sub-Saharan Africa during the early twentieth century. Instances of slavery still remain. The anti-slavery movement was only able to make progress in its goals over a number of generations. But it showed that, through repeated campaigns, it was possible to remould the international economy in line with moral principle.
Editor's note: This article was revised on February 25th, 2014 to add extra detail to the original version.