The Prison Letters of Nelson Mandela edited by Sahm Venter, with a foreword by Zamaswazi Dlamini-Mandela Liveright, 620 pp., $35.00

In a speech he gave after his release from prison in 1990, Nelson Mandela described the triumph of the South African anti-apartheid struggle he had done so much to lead. “We won peace standing on our feet, not kneeling on our knees,” he proclaimed with evident pride.

Mandela had joined the African National Congress in 1943, and when it was outlawed by the South African government in 1960 (weeks after the Sharpeville Massacre killed some seventy protesters near Johannesburg), he cofounded its armed militant wing, Umkhonto we Sizwe (MK). (MK began a campaign of bombings against power facilities and government posts that, prior to Mandela’s imprisonment, avoided human targets.) In 1962 he made a secret trip to several independent African nations and London, in search of funds and support for the fight against apartheid, and received weapons and sabotage training in Morocco and Ethiopia. Shortly after his return he was arrested, convicted of incitement and leaving the country without a passport, and given a five-year sentence. The next year he was prosecuted again, this time for sabotage, and in 1964, at the age of forty-five, Mandela was sentenced to life in prison. As grim as this was, many had expected that he would receive the death penalty.

In those days, few confidently predicted that the struggle against race-based minority rule in South Africa would have a peaceful outcome that blacks could be proud of. The country’s system of governance, based on legally entrenched and violently enforced segregation and white privilege, looked formidably strong at the time, and its leaders were determined to perpetuate apartheid. South Africa’s coffers were brimming with mineral revenues, boosting their confidence. There was little pressure for change from Western governments, whose attention to Africa was driven by the polarities of the cold war; as recently as the mid-1980s, they were still treating Mandela and the ANC as terrorists and Communists (Mandela himself remained on the US international terrorist list until 2008).

The cursory familiarity that many people today have with Mandela’s story of moral courage and triumph has produced a near-universal secular beatification. Mandela enjoys an image akin to that of Martin Luther King Jr. The late South African has, in other words, become an easy-to-claim hero. And in keeping with the often invoked King quote about the arc of the moral universe being long but bent inescapably toward justice—a particular favorite of Barack Obama—from the perspective of the present, Mandela’s ultimate triumph can feel deceptively predestined.

Mandela’s political journey, like that of his country, was far more complex. The black South Africa of the early 1960s did not yet have an obvious leader: it lacked not just a stirringly…