In 1951, shortly before they were detained by British authorities on suspicion of espionage, Burgess and Maclean defected to the Soviet Union. They both lived there under new identities and, according to official histories, as staunch supporters of Soviet communism. Some biographers, however, have suggested that the two Englishmen grew disillusioned with communism while living in the Soviet Union, and were never truly trusted by the authorities Moscow. When they died, however, in 1963 (Burgess) and 1983 (Maclean), the Soviet intelligence services celebrated them as heroes.

On Friday, the Soviet state recognized the two defectors in an official ceremony in the Siberian city of Samara, where they lived for a number of years, until the authorities relocated them to Moscow. Kuibyshev, as the city was known during Soviet times, was technically a vast classified facility where much of the research for the country’s space program took place. While in Kuibyshev, Burgess and Maclean stayed at a Soviet intelligence ‘safe house’, where they were debriefed and frequently interrogated, until their handlers were convinced that they were indeed genuine defectors.

At Friday’s ceremony, officials unveiled a memorial plaque at the entrance to the building where Burgess and Maclean lived. According to the Reuters news agency, the plaque reads: “In this building, from 1952-1955, lived Soviet intelligence officers, members of the ‘Cambridge Five’, Guy Francis Burgess and Donald Maclean”. On the same day, a letter written by Sergei Naryshkin, head of Russia’s Foreign Intelligence Service (SVR), one of the institutional descendants of the Soviet-era KGB, appeared online. In the letter, Naryshkin said that Burgess and Maclean had made “a significant contribution to the victory over fascism [during World War II], the protection of [the USSR’s] strategic interests, and ensuring the safety” of the Soviet Union and Russia.

Last year, Russian officials named a busy intersection in Moscow after Harold Adrian Russell Philby. Known as ‘Kim’ to his friends, Philby was a leading member of the Cambridge spies. He followed Burgess and Maclean to the USSR in 1963, where he defected after a long career with the British Secret Intelligence Service (MI6).