Donald Maclean Used Five Aliases to Betray the Washington Embassy
By Harlan Pryce ·
He spent two decades in the Foreign Office as a Soviet mole, leaving a trail of aliases and betrayed secrets before fleeing to Moscow in 1951.
American and British diplomats were blind to a traitor in their midst for two decades. The cost was a steady hemorrhage of state secrets from the heart of the Washington Embassy.
The file's catalogue entry records the identity of the man who facilitated this breach: Donald Duart Maclean. He was, by all outward appearances, a "high flying employee of the Foreign Office," the kind of man whose pedigree and polish served as an invisible shield against suspicion. In the circles he moved in, a certain social standing was often mistaken for an inherent lack of susceptibility to treason.
Richard Curzon and Four Other Men
In the clandestine service, a man is only as useful as the masks he can wear. The catalogue descriptions for files KV 2/4164, KV 2/4155, and KV 2/4159 list a dizzying array of identities used by Maclean to mask his movements and communications. He operated under the names Richard Curzon, Mark Frazer, Percy Maclean, and S Madzoevsky.
This was not a solitary performance. The records also note the role of Melinda Goodlett Maclean, an American and British national who shared in this shadow existence. Her own catalogue entries list aliases including Melinda Marling, Melinda Philby, and Natasha Frazer. When a spouse is integrated into the tradecraft, the betrayal is no longer just professional; it is a domestic arrangement built on a foundation of deception. The record indicates she was tied to Maclean’s movements, suggesting that the Soviet center viewed the couple as a combined asset, weaving their personal lives into the fabric of their espionage.
1951
The mask finally slipped in 1951. According to the catalogue entry for KV 2/4164, Maclean was identified that year as the source of a "leakage from the Washington Embassy some years earlier."
For those of us who have run assets, the phrase "some years earlier" is a bitter pill. It suggests a failure of counter-intelligence that spans a generation. Maclean had already moved through the ranks of the civil service—serving in Paris in 1938 and later ascending to head the American Department in the Foreign Office, according to the public record. He had spent years in the inner sanctum of Western diplomacy, likely reading the very cables that would expose the West's strategic vulnerabilities, while reporting directly to Moscow.
The Security Service eventually closed in, but the window of opportunity remained open just long enough. While under investigation, Maclean fled to the USSR. He did not go alone; he was accompanied by Guy Burgess. The two vanished into the East, leaving behind a vacuum of trust and a series of unanswered questions about how two men in such sensitive positions could slip through the fingers of their own government.
A Soviet Agent since the 1930s
The most damning assessment found in the catalogue record is the timeline. The Security Service, within its Personal (PF Series) Files on Soviet intelligence agents, assessed that Maclean had been a Soviet agent since the 1930s.
This means that for nearly twenty years, the British establishment trusted a man who had been compromised since his youth. It is a recurring theme in the history of the Cold War: the dangerous belief that class and education are substitutes for loyalty. The "high flying" status mentioned in the file was not just a career description; it was the very camouflage that allowed him to operate without scrutiny. He was the ideal asset because he fit the profile of the man the establishment believed could never be a traitor.
Maclean’s betrayal was part of a wider contagion, a ring of Cambridge-educated elites who viewed the Soviet project with more affection than they did their own oaths of office. While other archives, such as the UK National Archives' KV 2/4154 and KV 2/4160, hold further records on Maclean and his aliases, the summary in KV 2/4164 provides the essential autopsy of a failed vetting process.
He left behind a wreckage of compromised intelligence and a diplomatic corps forced to wonder who else among them was playing a part. The record leaves us to consider the specifics of that "leakage" in Washington—what exactly was handed over, and who in the embassy was too trusting to notice the leak while it was happening.