On November 16, 1979, British society was rocked to the core by the revelation that Sir Anthony Blunt – noted historian, Keeper of the Queen’s Pictures, and third cousin of the Queen Mother – had been a spy for the Soviet Union.

Blunt was named as the ‘fourth man’ in the ring of Cambridge-educated spies that also included Guy Burgess, Kim Philby and Donald MacLean; the three others had come under suspicion (and in Philby’s case interrogated), causing their flight to Russia in the 1950s and 1960s.

It was considered particularly shocking that Blunt had in fact confessed to espionage in 1964, some 15 years earlier, in exchange for information and immunity from prosecution, and yet was still working for the Royal Household.

The Queen and Anthony Blunt

His involvement in the ring had remained a secret until he was accused by journalist Andrew Boyle in his book Climate of Treason. On being questioned in the House of Commons, Prime Minister Margaret Thatcher revealed that Blunt was indeed the fourth man.

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Blunt was stripped of his knighthood and honorary Fellowship of Trinity College.  He withdrew from society, though continued to write on art history.  He died at his London home in 1983.