Cambridge Five

The Cambridge Five members

The known members of the Cambridge Five were Kim Philby, Guy Burgess, Donald Maclean, Anthony Blunt, and John Cairncross. They are known as the ‘Cambridge Five’ because they were recruited by Soviet intelligence during their time at Cambridge University in the 1930s. Having lost faith in capitalism, the Cambridge Five were eager to take up the cause of communism.

The successful long-term espionage of the Cambridge Five made a significant impact on Britain’s role in the Cold War, undermining Britain’s foreign policy during the period and the development of the nuclear deterrent. This Affair was particularly damaging to Britain’s special relationship with the United States. The successful long-term espionage of the Cambridge Five brought Britain's ‘Establishment’ into question.

Background of the Cambridge Five: the Second World War and the Cold War

The Second World War saw Britain and the USSR fighting on the same side against the Nazis. The Soviets took advantage of this alliance to plant spies in Britain to aid with their post-war plans of spreading communism and Soviet influence through Europe.

The Cambridge Five: the Burgess and Maclean affair

After spying on the British government for nearly two decades, Burgess and Maclean defected to Moscow, among rising suspicions. This is known as the Burgess and Maclean Affair. Burgess and Maclean spied for the Soviet Union during the Second World War and in the early Cold War period, which is said to have begun circa 1947–48.

After being recruited by the KGB, the USSR’s security agency, during their time at Cambridge University in the 1930s, Guy Burgess and Donald Maclean, along with the rest of the Cambridge Five, built careers within the upper echelons of the British Establishment.

Both Burgess and Maclean had privileged, well-connected upbringings, which set them up for success within the British government. Burgess was an Etonian before he attended university in Cambridge and Maclean’s father had been knighted and held the title of ‘Sir’.

Guy Burgess

Guy Burgess began supplying the Soviets with information on the British government during his time as a correspondent for the BBC, a position he took up in 1936. Burgess was known for being well-connected, and his conversations with MPs and politicians were invaluable for the Soviets.

Burgess juggled several high-ranking jobs during the Second World War, working for the BBC and both MI5 and MI6. Burgess’ connections sufficed to earn him a position at the MI6, where he was assigned to the propaganda division, Section D. It was Burgess’ standing in the Establishment that enabled him to acquire the position without being properly vetted.

In the MI5, he worked under the supervision of a fellow Cambridge alumnus. In 1944, he started working at the Foreign Office as a press officer. In 1950, Burgess began working with fellow spy ring member, Harold ‘Kim’ Philby, as the secondary secretary at the British Foreign Office in Washington, D.C.

Espionage

From his MI5 position, he was able to smuggle copies of nuclear weapons development documents to the Soviets and inform them of Britain’s plans to form the intergovernmental military alliance between Europe and the United States, the North Atlantic Treaty Organisation (NATO). Documents recently released in the Mitrokhin Archive show that Burgess delivered hundreds of top-secret documents to the KGB over the course of his career.

Donald Maclean

In 1935, after passing initial examinations to join the Diplomatic Service, Donald Maclean began working in the British Foreign Office. In 1950, he was promoted to head of the Foreign Office’s American department and helped draft Anglo-American policy. He was in England at the time suspicions rose about there being a spy in the Foreign Office by the name of ‘Homer’.

Espionage

From this position, Maclean was able to access and share Anglo-American policy regarding the Korean War, NATO, and the US’ nuclear capabilities and resources.

Fig. 1 - House in Samara, Russia, where Burgess and MacLean covertly lived between 1952-1955. The bottom right shows the commemorative plaque installed later.

Burgess and Maclean’s 1951 defection to Moscow

Cambridge Five double agent Harold ‘Kim’ Philby was working as the head of MI6 at the Foreign Office in Washington, D.C. when suspicions began to mount about the presence of a mole within the embassy, who went by the cryptonym of ‘Homer’. Philby sent Burgess, who was working at the embassy at the time, back to England to warn Maclean, under the pretence of ‘bad behaviour’.

Though Burgess was under no suspicion himself at the time, he defected to Moscow with Maclean. Their disappearance made headlines and the pair was correctly assumed to be spies. Suspicions of their defection would later be confirmed in 1956 when they appeared at a press conference in Moscow.

Harold ‘Kim’ Philby

In 1940, during the war, Philby began working with the British secret organisation, Special Operations Executive. In 1941, Philby joined MI6 and quickly rose in the ranks of British Intelligence, becoming head of Section IX, the Soviet counterintelligence section, in 1944. From 1949, he was stationed in the Foreign Office in Washington, DC.

Espionage

Philby worked as a double agent for the Soviet Union. Philby’s role as head of Section IX meant that all of MI6’s counterespionage efforts were completely undermined, as Philby would make his Soviet handlers aware of any developments. As head of Section IX, he had access to CIA and FBI documents and was briefed on any Venona Project developments: the mission of the Venona Project was to decrypt messages sent by Soviet Intelligence agencies written in secret code (cyphers).

Because Philby had access to this top-secret information, the Soviets stayed one step ahead of any possible code-breaking or knowledge of spy networks, which allowed suspected spies to defect before they were caught. This was the case for Maclean, who was able to defect because Philby sent Burgess to warn him.

Unmasking

After the disappearance of Burgess and Maclean, suspicion turned to Philby and after enough evidence against him was gathered, an investigation into Philby was launched in 1955.

In 1955, Harold Macmillan was working as Foreign Secretary in the Anthony Eden government and he cleared Philby of all charges. After weeks of interrogation, nothing incriminating was found but he was nonetheless discharged from his role as head of Section IX.

In 1963, Philby was finally unmasked by the testimony of Soviets who had defected to the West. Philby defected to Moscow where he lived until his death.

Anthony Blunt and John Cairncross, the other Cambridge Five

Anthony Blunt and John Cairncross both worked at Bletchley Park and provided the Soviets with German messages decoded by the British. Though the Soviets were allies of the British during the Second World War, they were not entrusted with British intelligence knowledge, which made Blunt and Cairncross’s espionage useful.

Anthony Blunt

Anthony Blunt was a respected, leading art historian before and after the war. He managed the art collection of the Royals as the Surveyor of the Queen’s Pictures. He was knighted in 1956 for his accomplishments in the role.

During the Second World War, he worked as a high-ranking intelligence officer for MI5. After the war, in 1947, he became director of the prestigious art college, the Courtland Institute of Art.

Espionage

While at Cambridge, Blunt helped recruit spies for the Soviets.

During his time with MI5, Blunt helped Burgess get a job there and he worked with spy-ring member John Cairncross at Bletchley Park, where German communications were decoded by British Intelligence. From this position, he passed on secret information regarding British code-breaking intelligence against the Germans to the Soviets.

His intelligence work mostly ceased with the culmination of the war, but he helped with the defection of Burgess and Maclean while pretending to help MI5 investigate Burgess.

Unmasking

Blunt was unmasked as the ‘Fourth Man’ by an American whom he had tried to recruit at Cambridge. He was subsequently questioned by MI5 in 1964 and confessed. He avoided prosecution by agreeing to share everything he knew. The Queen was made aware of his espionage, but he was allowed to keep his job as Surveyor to the Queen’s Pictures.

He kept his knighthood status until he was publically outed as a spy in 1979 by PM Margaret Thatcher and consequently stripped of his knighthood.

John Cairncross

During the war, John Cairncross worked as a German translator at Bletchley Park, where Anthony Blunt also worked. He began working under Philby in Section V - the counterintelligence section - of MI6 in 1944.

Espionage

As with Blunt, Cairncross’s position at Bletchley Park allowed him to provide the Soviets with any new information gathered by the British on the Germans.

After the war, he is believed to have alerted the Soviets about the development of Britain’s Nuclear Deterrent. According to Soviet defector Yurin Modin, Cairncross also provided the Soviets with information about NATO before the alliance was officially formed.

Cairncross maintained that his spying work was not detrimental to Britain, as the Soviets were allied with Britain during the Second World War.

Unmasking

Cairncross was the fifth and final member of the Cambridge Five to be unmasked. He was investigated by MI5 following the disappearance of Burgess and Maclean. He did not confess but agreed to abandon the civil service and moved to the US to pursue a career as a literary critic. In 1964, his link to Philby led him to be interrogated by MI5 once again and he finally confessed.

However, as with Blunt, he was given immunity from prosecution and continued his work as a literary scholar.

The public first became aware of Cairncross’s past as a spy when he confessed to journalist Barrie Penrose in 1979 and it was further confirmed by the testimonies of two Soviet defectors, including Modin’s 1994 book on the Cambridge Five.

The impact of the Cambridge Five on Britain’s Cold War role

The gradual unmasking of the Cambridge Five was a political embarrassment to Britain that threw the Establishment into question. The Cambridge Five undermined Britain’s Intelligence efforts in the lead-up to and during the Cold War, consequently impacting Britain’s foreign policy. They especially affected the special relationship with the United States, which in turn hindered the development of Britain’s nuclear deterrent.

The establishment

The Soviets realised that the weakness in Britain’s government was the networks of the British establishment. This led them to target Cambridge University, where the Five were recruited.

The Cambridge Five showed that the social networks that make up the establishment could easily be infiltrated and exploited: for example, the MI6 didn’t put Guy Burgess through a rigorous vetting process. Instead, his connections with and recommendations from other members of the Establishment were enough to get him a position within Britain’s foreign security service. Philby was cleared of all charges by at-the-time Foreign Secretary Harold Macmillan.

The successful long-term espionage of the Cambridge Five suggested that acquisition to the upper echelons of politics is dependent on connections within the establishment, which in turn implied that this was a flawed, unfair, and outdated system. The media attention that Burgess and Maclean’s defection to Russia received was a factor in bringing about thirteen years of Conservative government during the Consensus years, as their defection, alongside the Profumo Affair scandal, put the integrity of the Conservative Macmillan government into question.

Macmillan and his replacement, Alec Douglas-Home, were both members of the establishment. By the general election of 1964, the public had grown disillusioned with the Conservatives, who came to be synonymous with the establishment.

The Cambridge Five hampered Britain’s role in the Cold War

The Cambridge Five compromised British Cold War intelligence, the nuclear deterrent, and the special relationship between Britain and the US.

Compromised British Cold War intelligence

The successful espionage of the Cambridge Five threw the effectiveness of Britain’s intelligence operations at the time into question.

Philby’s appointment as head of Section IX meant that all counterintelligence work carried out under his supervision was completely ineffective, as he passed on all information to the Soviets. Burgess managed to inform the Soviets of the US plans to form the North Atlantic Treaty Organisation (NATO).

The nuclear deterrent

Maclean and Burgess, for example, both had access to highly classified information on the development of nuclear weapons and smuggled copies of these documents to the KGB. This meant that the US and Britain’s advancements in the Cold War arms race was to an extent undermined by the Cambridge Five.

The special relationship

For a decade after Burgess and Maclean’s defection, Britain and American intelligence forces shared only limited information, as America’s trust in Britain had been broken. Over time the trust between the two nations was rebuilt, but the rift between the two nations slowed down the development of Britain’s Nuclear Deterrent.