Marxism in Britain has declined, almost to the point of oblivion, since the Second World War. The Communist Party of Great Britain had more than 50,000 members in the early 1940s, but less than 5,000 when it disbanded in 1991. Dissenting and Trotskyist organizations experienced a very similar decline, although there has been a late flowering of Marxism in Scotland.

Based on the Communist Party archives at Manchester, Marxism in Britain examines the decline over the last sixty years. The book deals with the impact of the Cold War upon British Marxism, looking at how international events such as the Soviet invasions of Hungary and Czechoslovakia affected the Communist Party of Great Britain. The issues of Marxism and Britain's withdrawal from the Empire are also addressed, as are the Marxist influence upon British industrial relations and its involvement in the feminist movement. Keith Laybourn focuses very much on the current debate in British Marxist history which divides historians over the influence of Moscow and Stalinism on the Communist Party, and he explores the ways in which this undermined Marxism in Britain.