This magisterial volume, a sequel to Britain’s Imperial Century, 1815–1914 (1976), is the distillation of a lifetime’s learning and teaching about the British Empire. The earlier work, Ronald Hyam explains, was a kind of ‘user’s handbook’. The present study, based on mountains of documentary evidence, concentrates more specifically on the politics of decolonisation. Such a rigorous scholarly enterprise would have every excuse to be dry. But as became instantly apparent to his Cambridge pupils (of whom, to declare an interest, I was one), Hyam is entertaining, incisive and sardonic to the point of ribaldry.