The Cambridge Five was a ring of spies in the United Kingdom that passed information to the Soviet Union during the Second World War and the Cold War and was active from the 1930s until at least the early 1950s. None of the known members were ever prosecuted for spying. The number and membership of the ring emerged slowly, from the 1950s onwards.[1]
The general public first became aware of the conspiracy in 1951 after the sudden flight of Donald Maclean (1913–1983, codename Homer) and Guy Burgess (1911–1963, codename Hicks) to the Soviet Union. Suspicion immediately fell on Kim Philby (1912–1988, codenames Sonny, Stanley), who eventually fled to the Soviet Union in 1963. Following Philby's flight, British intelligence obtained confessions from Anthony Blunt (1907–1983, codename Johnson) and then John Cairncross (1913–1995, codename Liszt), who have come to be seen as the last two of a group of five. Their involvement was kept secret for many years: until 1979 for Blunt, and 1990 for Cairncross. The moniker Cambridge Four evolved to become the Cambridge Five after Cairncross was added.[1]
The group were recruited by the NKVD during their education at the University of Cambridge in the 1930s, but the exact timing is debated. Blunt claimed they were not recruited as agents until after they had graduated. A Fellow of Trinity College, Blunt was several years older than Burgess, Maclean and Philby; he acted as a talent-spotter and recruiter.[2]
The five were convinced that the Marxism–Leninism of Soviet communism was the best available political system and the best defence against fascism. All pursued successful careers in branches of the British government. They passed large amounts of intelligence to the Soviets, so much so that the KGB became suspicious that at least some of it was false. Perhaps as important as the specific state secrets was the demoralising effect to the British establishment of their slow unmasking and the mistrust in British security this caused in the United States.
Many others have also been accused of membership in the Cambridge ring.