Sentencing the leaders of the ANC in 1964 to finish their lifetimes on Robben Island, the apartheid courts did the movement an unintended, and horribly delayed, favour. Imprisonment not only forged unbreakable bonds, it also brought generations and rivals together, and taught them to argue, debate, disagree and then unite. For this, which contributed so much to what Elinor Sisulu describes as the miracle whereby apartheid died a tidy death at the negotiation table rather than on bloody streets, South Africans can be very thankful. Chief among the jail heroes is Walter Sisulu, whom Nelson Mandela in his foreword calls "a giant and cornerstone", a born mediator, wise yet uncompromising.
Born in 1912, the same year as the ANC, his father was a white magistrate's clerk who acknowledged his children by Alice Sisulu but never wished to know them. Walter grew up with his sister in a traditional Xhosa family, migrating in his twenties to Johannesburg, where he married Albertina, a student nurse. He died earlier this year, on the eve of his 91st birthday.
This joint biography of their lives together and apart falls into three main periods, starting with the 1940s and 1950s, when their country moved against the trend towards majority rule but political activity was still possible. Walter was the ANC general secretary, Albertina the rock who cared for their five children and many cousins and orphans. The following two decades were dark, exile or prison being the stark choice, with hope largely extinguished until the Soweto schools uprising of 1976 showed the power - and costs - of popular resistance.
With Walter in jail, Albertina's life was made harder by banning orders, police harassment and the detention of her children. Then came a tumultuous decade of struggle and suffering before dawn began to break.
Among many terrible events was the killing of Albertina's colleague Dr Abu Asvat, shot in the consulting room of their township clinic. It was like seeing her own son murdered, she said. Asvat's death was compounded by the apparent involvement of Winnie Mandela's notorious football club. Horrified though she was, Albertina refused to publicly attack a comrade.
But, increasingly, she took up Winnie's mantle as mother of the nation, using invitations from Mitterrand and Bush senior to appeal for pressure on Pretoria. Homeward-bound, she was unexpectedly asked to meet Margaret Thatcher, otherwise apartheid's main defender. Albertina was not impressed: Thatcher lectured instead of listening. But all was evidence of the tortuous process whereby, in 1990, the liberation organisations were unbanned and the leaders freed to play their parts in the transition to democracy.
The dense detail of these lives is skilfully ordered by the author, a Zimbabwean academic who married the Sisulus' son Max in exile. Her historical narrative is enlivened with family events that also show how profoundly the political affected the personal over five decades. Most moving is her account of the eventual reunion. Albertina was still sleeping at 5.30am as Walter arrived in a police convoy at their Soweto home: a small miracle of its own, for over 30 years hope "in our lifetime" must often have had a hollow ring.