Portrait of Alan Mathison Turing, 1951 (bromide print)

One of Britain's most influential mathematicians and computer scientists. Born in London, Turing studied at King's College, Cambridge. Throughout the Second World War Turing worked for the Government Code and Cypher School at Bletchley Park. Known to colleagues as 'Prof', Turing was central to the breaking of the German naval cipher, the Enigma. After the war he joined the National Physical Laboratory where he led the work to develop a large-scale electronic digital computer. In March 1952 Turing was brought to trial for having a sexual relationship with a man. His position as a government consultant was ended. On 8 June 1954 Turing was found dead, the inquest ruled suicide by cyanide.