Every Thursday at one point during Nelson Mandela's long incarceration on Robben Island he and a group of other black prisoners would be taken outside and told to dig a trench six feet deep. When it was complete, they were told to get down into it, whereupon their white warders would urinate on them. Then they were told to fill in the trench and go back to their solitary cells.
Years later, when Nelson Mandela was about to be inaugurated as the first president of South Africa elected by all its people, he was asked who he would like to invite to his first dinner as president. The warders from Robben Island, he said. "You don't have to do that," his advisers told him. "I don't have to be president either," he replied. The first time he sat down to break bread as head of state those same warders were his guests.
When Nelson Mandela arrived in London last week for the unveiling of his statue in Parliament Square, most of those who turned out to offer him adulatory applause were, like me, middle-aged and upwards. Mandela's epic life was the political soundtrack to our formative years.
In the politics of the 1960s, the apartheid system in South Africa stood as a totem of all that remained of the entrenched privilege and evil repression of the imperialism of the past. Apartheid was the last bastion of the arrogant notion of the superiority of the white man.
Stories like the one about the whites pissing on the blacks were the fuel for the outrage of the anti-apartheid movement all around the world. The curved black and white circle that was its badge became an icon for an entire generation. And Nelson Mandela became its hero.
Mandela was one of his nation's first black lawyers. He had set up the first African law firm in South Africa with his partner, Oliver Tambo, in 1952. The two men campaigned against the repressive system.
In 1960, tensions soared when 69 black people were shot dead by police in the Sharpeville massacre. The government banned the principal black political opposition, the African National Congress. "All lawful modes of expressing opposition," Mandela later said, "had been closed by legislation, and we were placed in a position in which we had either to accept a permanent state of inferiority, or to defy the government."
Peaceful resistance was over. Mandela became the leader of the ANC's armed wing, Umkhonto we Sizwe (Spear of the Nation). He went into hiding, declaring "the struggle is my life". Even then his commitment to violence was a tempered one. Umkhonto limited itself to sabotaging military and government targets. Its members were told they were on no account to injure or kill anyone and were forbidden to carry weapons.
But he also toured the world to raise support for a guerrilla army should sabotage fail to end apartheid. He was received with great sympathy across Africa and also by Labour and Liberal political leaders in London. Thirty years of ANC moderation had only ever produced laws restricting the rights and progress of the majority black population.
Yet that was enough to secure a guilty verdict when Mandela returned to South Africa and was caught by the authorities.
At the Rivonia treason trial Mandela set out a cogent defence in a speech which it is still moving to read today – and which electrified the world when it was delivered in the closing moments of a trial in which the prosecution had asked for the death penalty. It ended: "During my lifetime I have dedicated myself to the struggle of the African people. I have fought against white domination, and I have fought against black domination. I have cherished the ideal of a democratic and free society in which all persons live together in harmony and with equal opportunities. It is an ideal which I hope to live for and to achieve. But if needs be, it is an ideal for which I am prepared to die."
Mandela was jailed for life. He was to serve 27 years behind bars. But the anti-apartheid struggle continued, led by South Africa's churches and black children in the townships, supported by demonstrations by students and political activists across the globe.
Britain was a particular focus. The then Bishop of Liverpool, former England cricketer David Shepherd, was a vocal opponent. The world community imposed limited economic sanctions on South Africa.
News of the conditions on Robben Island only fuelled the international fury. Mandela performed hard labour in a lime quarry. Conditions were very basic. Prisoners were segregated by race, with blacks receiving fewest rations. Mandela was allowed one visitor every six months, and one letter, often rendered unreadable by the prison censors. When his mother and eldest son died, he was not allowed to attend their funerals.
Then in 1980 the exiled Oliver Tambo launched an international campaign whose "Free Nelson Mandela!" slogan resounded through universities, churches, schools and trade union gatherings across Europe and America. Local councils began to name streets, squares and buildings after Mandela. Musicians dedicated songs to him.
So embarrassing was the international outcry, and so hurtful the economic sanctions, that in 1985 the white president, P W Botha, offered to release the world's most famous prisoner, so long as he renounced armed struggle. Mandela refused with the words: "Only free men can negotiate. A prisoner cannot enter into contracts."
Support for Mandela and his cause was not universal. Reactionary politicians including the Prime Minister, Margaret Thatcher, in the UK, and, in the US, Dick Cheney (now Vice-President) supported the apartheid regime and insisted that Mandela was a terrorist. But they were an increasingly small minority in the civilised world. On Mandela's 70th birthday a massive concert was held at Wembley featuring a host of leading musicians.
Three things brought change. The international campaign was one. The second was that Archbishop Desmond Tutu, on whom the mantle of leadership had fallen with all the ANC leaders jailed or exiled, had travelled repeatedly to the United States and persuaded key American financial institutions to disinvest in South Africa. The third was that, in 1989, President Botha had a stroke and was replaced by F W de Klerk. The new white president saw the writing on the wall, with sanctions biting and the nation's isolation growing. On 11 February 1990 Mandela was freed from jail.
The world watched his release and heard his first words of freedom: "I stand here before you not as a prophet but as a humble servant of you, the people. Your tireless and heroic sacrifices have made it possible for me to be here today. I therefore place my life in your hands."
Within three years Mandela and de Klerk had jointly been awarded the Nobel Peace Prize. Within four years the black leader had replaced the white one as president. At his inauguration as the nation's first president elected by the whole population he said: "We dedicate this day to all the heroes and heroines in this country and the rest of the world who sacrificed in many ways and surrendered their lives so that we could be free .... Their dreams have become reality."
Yet the most astonishing thing was to come. Mandela invited to his inauguration his arch enemy P W Botha and also Percy Yutar, the lawyer who had tried to get him executed in the Rivonia trial. He then went out of his way to support the all-white national rugby team, the Springboks, wearing a team shirt during the 1995 World Cup. And he threw his weight behind Desmond Tutu's idea for a Truth and Reconciliation Commission, which offered amnesty to all those who came forward to fully confess their crimes during the apartheid regime. This policy of reconciliation averted a bloodbath and eased the transition to multi-racial democracy.
This was his most extraordinary achievement. Ironically its roots lay in the long years of imprisonment.
In jail, he said, "You come face to face with time: there is nothing more terrifying." There he learned the power of forgiveness. Though as a boy he was educated at Methodist colleges, Mandela had no personal religious faith as motivation. But his long years in prison inculcated in him an extraordinary tolerance and compassion, and brought him a sense of perspective that enabled him to see beyond day-to-day politics to more ultimate ends.
It enabled him to exert authority over the warders, and eventually over the South African government itself until they were virtually his prisoners and he was the warder. Afterwards he never reminded anyone of their past support for apartheid or its horrors. And when angry young ANC activists called for vengeance he replied that if he could work with enemies who sent him to jail for a third of his life, so could they.
Reconciliation was the price of future peace. "Men of peace must not think about retribution or recriminations," he said. "Courageous people do not fear forgiving, for the sake of peace".