The anniversary of the abolition of the slave trade by the British parliament on 25 March 1807 is being commemorated with a series of events, exhibitions, books, articles and public debates. This is a welcome opportunity to increase public understanding of the brutal experience of slavery and the systematic violation of humanity it embodied.

But to recall the facts of this history is also to resist the temptations of the comforting, even celebratory attitude to history that attends at least some of the bicentennial commentary. For the abolition of the trade in one of its chief centres was neither the ending of slavery itself (that would take many more years) nor (as it is sometimes portrayed) a straightforward story of benevolent heroism by the abolitionists. Moreover, the effects of this ghastly trade and institution continue to mark our world, two hundred years on.

This article puts 1807 in the context of what went before and what came after, and suggests that in 2007 the legacy of the slave-trade is very much alive and in need of practical engagement by citizens, scholars and inheritors on all sides.

Marika Sherwood is a senior research fellow at the Institute of Commonwealth Studies, London. She is the author of After Abolition: Britain and the Slave Trade Since 1807 (IB Tauris, 2007)

The slave trade

Queen Elizabeth I of England did not need much persuading to support Sir John Hawkins's expeditions to west Africa in the 1560s to obtain slaves. Britain was not the first European power to indulge in this abhorrent activity: Spain had exported about 23,000 Africans to her colonies in the Americas by the time Hawkins and the queen entered the profitable trade. All who could - the Dutch, the French, the Danes - joined in.

But in 1750, Britain gained control of the trade; and in the next twenty-five years, about 3,552 vessels sailed from Britain on slaving voyages. The number of Africans transported in British ships from 1750-1807 is estimated as 2.25-2.5 million. The total number of men, women and children exported until 1810 is believed to have been about 7.5 million; and from then until around 1860, another 2 million were seized and sent across the Atlantic.

To these horrific numbers, many more must be added: those who died in the process of enslavement, those who died in the "barracoons" on the west African coast while awaiting shipment, and those who died on the voyages to the Americas in the overcrowded, grossly packed slaving vessels. A book published by Seeleys of London in 1850, A Cry from the Middle Passage, estimated the "casualty" rate of transported slaves at 25%; an assessment of the true scale of the African slave-trade must take this huge attrition into account.

Why did Europeans, when their own serfs were gaining their freedom, export Africans? The new world was goldmine to its European "discoverers" and exploiters. But to extract its riches, labourers were needed: the local populations had rapidly been decimated, if not exterminated, by the wars of conquest and European diseases; those left alive had no wish to labour for their conquerors. The number of indentured labourers from Europe was insufficient, and many naturally escaped their servitude as quickly as they could. So why not import enslaved labour - especially from areas whose inhabitants could be expected to stand up to the climate?

The slave institution

Many different forms of slavery have existed throughout the centuries in a wide spectrum of societies. The conditions of slaves also varied hugely, in length of bondage or the degree of restriction imposed. A person could be enslaved for a particular purpose (to serve in the military, or in a harem, or in a household). In particular social orders, "slavery" was akin to what in Europe was called serfdom.

Slavery could be for life or for specified periods; slaves might be able to marry each other or even into the family, clan or tribe that had enslaved them. Slaves might retain their status in perpetuity or be absorbed into the community they served and thus eventually lose slave status. In some societies, a slave could rise in the social structure and attain high rank.

In the context of this history and plurality, how Europeans behaved towards enslaved Africans in their colonies was unique. With some exceptions, enslaved women, men and children were not treated as human beings. They were sold in the colonies as if they were cattle or bags of sugar. They were stripped of their names, and often were not permitted to speak their language, practice their own religions or customs, or marry. They could be bought and sold (children often separately from their parents), beaten, whipped, tortured, and raped. They were at the total, unrestricted mercy of their owners. And this was the first instance of racial slavery.

The process of abolition

Denmark passed a law interdicting slave trading in 1792, which came into force in 1803. In Britain the campaign against the trade began in the 1780s and was led by Quakers and black residents of the country. Granville Sharp took cases to court; Thomas Clarkson collected evidence; two former slaves, Ottobah Cugoano and Olaudah Equiano, published books; and other London blacks addressed meetings. Clarkson and Equiano spoke to large gatherings around the country (the latter's An Interesting Narrative of the Life of Olaudah Equiano, or Gustavus Vassa, the African went into nine editions in Equiano's lifetime and several more - often adulterated - were published after his death in 1797. It remains in print).

Anti-slavery associations were formed; women (given no voice by the men) formed their own organisations and campaigned more practically by pleading for the disuse of slave-grown sugar. Petitions with hundreds of thousands of signatures poured into parliament. William Wilberforce agreed to present abolition bills in the House of Commons. In the era of war with France in the 1790s, enthusiasm diminished; but after over twenty years of struggle, and with a new political party in power, the Abolition Act was passed in 1807.

The abolitionists' efforts in the "mother country" were noble. In the colonised territories, the enslaved themselves were a major force and agency of their own emancipation, and added indispensable reinforcement to the abolitionists' cause. In the West Indies, slaves revolted, burnt crops, and escaped into the hills. A revolt in the French colony of St Domingue during 1792-1800 was successful: the French were expelled, freedom proclaimed, and the country renamed Haiti (see CLR James's classic account, The Black Jacobins, 1938).

Britain, using troops from the homeland and West Indians, attempted without success to conquer the Haitians. France's national convention abolished slavery in 1794, but Napoleon reinstituted it in the remaining French colonies. Only in 1815, at the end of the era of revolutionary wars, did France make it illegal to trade in slaves. A parallel process occurred in north America, where most of the northern states (i.e., those without plantation economies) gradually abolished both slave-trading and slavery itself after the war of independence from Britain. In 1807, the United States Congress prohibited slave trading by Americans.

In the British parliament, the struggle for the slaves's freedom took as long as the struggle for abolition of the trade: it took until 1833 for the Emancipation Act to be passed. Even afterward, slaves were expected to serve long "apprenticeships"; but increasing numbers of slave revolts made enforcement impossible, and freedom was declared in 1838. The British government (with the help of Rothschilds, the bankers) distributed £20 million - the equivalent of about £1 billion today - to the deprived slave-owners in the West Indies. The freed women, men and children received nothing at all, except the opportunity to work for the paltry wages that were now being offered to them.

After the abolition of the trade, Britain had exerted considerable pressure on all other countries trading in enslaved Africans to cease their lucrative business. After emancipation, Britain did not free all its own slaves. Slavery continued in India until the 1860s; in Britain's protectorates in Africa (later colonies), the final acts were passed only in 1927 (Sierra Leone) and 1928 (Gold Coast).

Meanwhile, in the United States, it was not until the end of the civil war (1865) that slavery was ended (Britain declared its neutrality in the war, but ties of economic dependence meant that it provided massive financial and shipbuilding support for the confederate side). Slavery had already been abolished in Chile (1823); in Mexico (1829); and in the French colonies (1848). It was ended in Cuba in 1886 and in Brazil in 1888.

After abolition

The evidence indicates none of the countries which made it illegal to trade in slaves followed through by actually stopping participation. Britain made the most noise after 1807, but many of its subjects who benefited from a rewarding enterprise saw no reason to desist just because parliament had declared their actions illegal. The only attempt to enforce the 1807 act was the creation of the anti-slave-trade squadron, which for most of its existence was undermanned, and equipped with vessels too slow, too old and unsuitable for West African waters.

The abolitionists continued to campaign on the issue by informing the House of Commons (and when Henry Brougham was created a lord, the House of Lords) of the many and various infringements and methods of circumvention. Parliament called innumerable committees and commissions to investigate; an immense amount of evidence was gathered, at equally immense cost. More acts were passed, and the legislation was twice consolidated; but - if the reports of British consuls in Cuba and Brazil, and the most assiduous of the captains of the anti-slave-trade squadron, are to be believed - it was all to no avail.

Slaving vessels continued to be built in Britain; their special fittings were installed either in Britain, or in convenient and complicit ports overseas. British bankers and insurers bankrolled and insured the vessels and their voyages, and slave-worked enterprises. British manufacturers continued to produce the articles used on the west African coast in exchange for human beings. British companies created partnerships with slave-traders and slave-worked plantation-owners in the southern United States, and in Cuba and Brazil. Britons also continued to own slave-worked mines and plantations.

The British governing class's true attitude was further revealed when the import duty on free-grown and slave-grown sugar was equalised in the 1840s. It was pointed out to the government during parliamentary debates that this would inevitably increase the import of slaves by Cuba and Brazil. Britain cared not, as it cared not about the massive importation of slave-grown cotton from the American south. 80% of the cotton used in the industry of Lancashire, northwest England, was slave-grown: the ever-growing and (for a few) prosperous cities of Manchester and Liverpool were dependent on slavery. British exports too continued to rely on slavery to a considerable extent (see After Abolition: Britain and the Slave Trade Since 1807, IB Tauris, 2007).

A bitter legacy

The effects of slavery - as trade and as institution - are present today. In the Caribbean, the exterminated native peoples were replaced by Africans. After emancipation, indentured labourers from India were imported to the British-ruled islands. This new mixed population is still struggling to create peaceful coexistence, while attempting to establish an identity that does not begin with enslavement. A difficult inheritance was compounded by the fact that land was mainly owned by whites, leading to forced emigration: to other islands, to the south American mainland, to north America, to Britain.

The impact on west Africa of the loss of millions of their most able-bodied people across many decades is immeasurable. It contains many dimensions, large and small, visible and invisible. Those remaining experienced endemic insecurity, both economic (the destruction of local industries such as weaving, tin, and iron by cheaper imports) and psychological (slave-traders had encouraged and instigated wars by selling guns and gunpowder in exchange for slaves, creating a climate of threat whose remnants survive to this day).

Slavery continued in the British colonies for decades after 1807 and 1833. The arrival of "legitimate trade" (for example in palm oil) required large plantations, so various forms of "domestic slavery" were installed. Mines also required such labour, as did the British government's engineering (e.g road-building) projects. This "contract labour" (as it was usually called) meant that when workers were needed to build roads or bridges, local chiefs had to furnish workers for the requested period of time, irrespective of the food-growing cycle. If the chiefs were reluctant, force could be used.

The legacy of the trade is equally great in Britain itself: in the accumulated wealth embodied in the country's businesses and architecture, in the survival of the racist attitudes that were engendered to support the enslavement of Africans, and in the living presence of millions of people whose ancestors were slaves or involved in the slave trade. The distance from 1807 to 2007 is but a short step. The past remains to be overcome.