Slavery: Abolished 200 years ago? Tell that to the people in chains

The wind was fierce and freezing. The cars moved slowly on the Humber Bridge, drivers concentrating hard. Few can have noticed the small group of men, women and children on the walkway, high above the river. Some were shuffling, not walking, because they were bound together by the iron chain looped around their wrists. Three men wore a wooden yoke on their necks that would snap vertebrae if they stumbled.

"So sorry," said the words on the black T-shirts worn over waterproofs by these men, locked in a bondage not seen in Hull since the docks in the distance dealt in human cargo. Slaves.

"Our hope is that this form of apology will speak in ways that words cannot," said David Pott, the slender, softly spoken 60-year-old who is leading a 250-mile walk in chains from Hull to London. It is "a kind of pilgrimage" to mark the bicentenary of the Slave Trade Act, which was given royal assent in 1807 and made slaving illegal. They also want to draw attention to the 12.3 million people that the United Nations estimates are caught in modern forms of slavery.

The campaigner given most credit for the Act was William Wilberforce, subject of a new film, Amazing Grace, about to be released. His great-great-great-grandson of the same name left the Wilberforce home city of Hull with the walkers on Thursday morning. "I wanted to do something more than go to all the functions," said Mr Wilberforce, a 48-year-old accountant from Yorkshire. He praised the efforts of campaigners such as Thomas Clarkson and Olaudah Equiano, who will get less attention than his ancestor, "as well as the slaves themselves, who resisted the trade bravely".

The bicentenary will be marked this month by hundreds of official events at museums, theatres, galleries, schools and churches across the country, put on with the help of £16m from the Heritage Lottery Fund. Baroness Scotland will visit west Africa this week, but the first event on the list was the March of the Abolitionists, a grand name for what will be - most of the time - a small group of people enduring blisters, bruises from the chains and the indifference of people they pass. At the end of the long road will be a service in Westminster with the Archbishops of York and Canterbury.

The irony of the bicentenary is that the 1807 Act did not end slavery at all: it was not abolished in Britain for another 26 years, and in the US for another 58. And some say it has never really ended at all. The walkers are all supporters of Anti-Slavery International, which was founded in 1839 but which still campaigns today.

To the UN, modern slaves includes those caught in bonded labour, child labour and sexual servitude. Bonded labour can mean whole families working for almost nothing for decades to pay off small debts, such as $20 or so borrowed from a farm manager in India to buy medicine for a baby. The UN says some families on farmland in south Asia are "kept like cattle".

Up to 8.7 million children are in life-threatening forced labour. They include brides such as Naseema, married to a neighbour in Afghanistan by her mother at the age of four. Starved, tortured and made to act as a slave to his extended family, she was even forced to lie down as a human table from which the family ate.

Modern slavery also exists in this country: last week The Independent on Sunday revealed that up to 5,000 children are being forced to work as sex slaves here.

The figure came from the Joseph Rowntree Foundation (JRF), which carried out a study with the University of Hull and Anti-Slavery International. Together they define slavery as "severe economic exploitation; the absence of a framework of human rights; and control of one person over another by the prospect or reality of violence".

Workers in Asia and Eastern Europe may be tricked into paying "recruitment fees", for example, only to find themselves in squalid and dangerous conditions here. They work illegally for a pittance with their passports taken away, said Julia Unwin of JRF. "Those who protest may be beaten, abused, raped, deported or even killed."

Tony Blair has just agreed to give legal protection to victims of trafficking - but he has resisted calls to offer a formal apology for the trade that saw two million slaves pass through ports such as Bristol and Liverpool.

David Pott wants every leader whose country was implicated to offer an "apology of substance". To provoke that is one reason why he has walked in chains through slave sites in Europe, the Caribbean and the US over the past seven years. The people who understood and responded to this most deeply were the most African, he said. "Western culture is individualised; we have lost our sense of community. Some African people still have a very strong sense of what was done to their forebears."

Mr Pott is gentle, bearded and polite. Just the sort of white man to wring his hands with guilt about a colonial past that is best forgotten, you might think. But then the walkers come off the bridge and you realise that a third of them are black.

Monette Tapa-Mekomou was born in Martinique, a descendant of slaves - although she found that out only when an African friend heard her hum the nonsense lullaby her mother once sang. It turned out to be in a language from central Africa, as sung by a homesick slave locked in the bowels of a ship. Tracing her family history has proved impossible. "The masters destroyed everything about each slave's identity," she said.

So what did she have to apologise for? "Bitterness," she said. "Firstly, I receive the apology from the Caucasians. I have seen Africans break down in tears when they hear it. But as descendants of slaves we carry much bitterness towards Europeans and Africans who sold us into slavery."

And towards the church. Mr Pott and Mrs Tapa-Mekomou are evangelicals who believe symbolic gestures like theirs have a wider significance. So were Wilberforce and others who fought slavery. But the Church of England owned plantations. The Bishop of Exeter received £13,000 compensation when his slaves were freed. "The masters thanked God for the human cargo they had locked in the hold," she said. "As a Christian I am sorry for that. But their God is not my God."

After 16 miles the walkers warmed up in the impressive riverside eco-centre at Barton-upon-Humber. The mayor was there to pump cold hands, along with other prominent locals (although they did not quite seem to know what to make of it all).

Mrs Tapa-Mekomou said she was used to people being nonplussed. "I see a lot of denial. Black people are ashamed of their history as slaves and want to ignore it. White people don't want to talk about it either, or the slaves in the world today. They prefer to believe it is all history."

Her son Michael, 13, was with her. Across the world, children his age are working in sweatshops or as sex slaves. Stumbling through Humberside with white men in chains was the way she had found to make a few people face up to that. "We are like a dysfunctional family that will not talk about what is really happening," said Mrs Tapa-Mekomou. "What we are trying to do here is to say, 'Let's talk. Let's stop this cycle of lies and denial about slavery. And let's admit that people are suffering right now.'"

How 12.3 million people in the world today became slaves

TRICKED Malik, 12, from Mali, was sent by his parents to a teacher of the Koran, who said he was travelling to Niger with other boys to study

SOLD Nayla from Azerbaijan was nine-years-old when she was removed from a children's home by her mother and sold to people traffickers

HIRED Serena left the Philippines to work in Saudi Arabia as a housemaid, a job that she thought was perfectly legitimate. All the papers appeared to be in order

IN DEBT Raman was born at the brick kiln in India where his father and grandfather worked all their lives to pay a $450 debt to the manager

CHILD LABOUR Malik and the other boys were denied schooling in Niger. Instead they were forced to act as street beggars for the fake teacher

SEX SLAVERY Nayla was prostituted in Dubai clubs then deported at 13. She contracted Aids and gave birth to an HIV-positive baby

FORCED LABOUR Serena was locked in the house and her passport taken. She was beaten, abused and pushed down the stairs

BONDED LABOUR The family earns 2 cents for every 80kg of bricks. The manager beat them. He promised to hunt them down if they ran away

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