Naomi Mitchison began her novel-writing career in the 1920s, with historical fictions set in the Ancient world, in Roman and Greek civilisations, and soon won a high reputation world-wide.But she began to move toward present and future as well as past: thus Lobsters on the Agenda (1952) dealt with contemporary Highland life. When in her sixties she began a lasting friendship with a young chief designate of the Bakgatla tribe, Linchwe, she went on to join the tribe, and was adopted as its Mother. She wrote only one adult novel about Botswana, When We Become Men (1965). This fine novel deals with the contemporary fight for equality across southern Africa, and the struggle against apartheid. It ends up projecting towards a future where fighting would be unnecessary.Her main character here is Isaac, a young man brought up in Pretoria, who believes in resistance to a white minority government, and, like Nelson Mandela, backs bloodless sabotage as a political weapon. He deeply distrusts the remnants of the tribal system, and the power of the chiefs. He meets Letlotse, young heir apparent to the Bakgatla, returning home from an expensive but sometimes bizarre or just irrelevant education in Britain. He distrusts old ways too, and is tempted towards national politics, away from the tribe.There are clashes of beliefs, and conflicting ideas and loyalties. There is violence here. There are rapes and murders, and some killings that the Africans regard rather as executions. Here is a vivid, clear account of a troubled people in transition, which helps the reader to understand and empathise with the birth-pangs of a new, post-Imperial, Africa.Isobel Murray is Emeritus Professor of Modern Scottish Literature at the University of Aberdeen