Alexander Ulanovski and the 1935 Espionage Trials in Holland and Denmark
By Vera Kessler ·
An officer of Soviet Intelligence survived arrests in two European nations only to operate in the United States, a career trajectory kept in a personal file for decades.
The cost of Alexander Ulanovski’s career was paid in the currency of national betrayal across three continents, leaving a trail of compromised officials and broken trust from the North Sea to the Atlantic. He was a man who specialized in the art of the deep entry, a professional who viewed the borders of sovereign states as mere suggestions, provided the Kremlin’s objectives were met.
This story is reconstructed from a catalogue description of a personal file held by the UK National Archives, a summary that stands in for the original pages.
"arrested and tried on charges of spying"
In 1935, the operational life of Alexander Ulanovski—who frequently operated under the alias Nicholas Sherman—collided with the legal realities of Northern Europe. Ulanovski was a Russian operative for Soviet Intelligence, the sequence of secret police organizations that enforced the will of the Kremlin through terror and infiltration. By the early 1930s, he had spent a decade engaged in "Soviet espionage and subversion worldwide" (KV 2/1418).
His activities centered on Holland, the maritime and economic power on the western coast of the Netherlands, and Denmark, the Nordic metropole of the Danish Realm. In both jurisdictions, the local authorities finally caught up with him. The record is blunt: in 1935, he was "arrested and tried on charges of spying" (KV 2/1418).
To be arrested and tried in two different countries in a single year is usually the end of a spy's utility. For most, it is the moment they are traded in a prisoner exchange or left to rot in a foreign cell. But Ulanovski was not most operatives. The public record of the 1930s shows a Soviet intelligence apparatus that was increasingly professionalized, moving away from the amateurism of early revolutionary cells toward a structured cadre of career officers. Ulanovski was a product of this shift.
The Hierarchy of the PF Series
There is a critical distinction in how the Security Service, the internal intelligence agency tasked with protecting the United Kingdom from espionage, archived its targets. The Security Service maintained separate classifications for those it watched, a divide that reveals who the Soviets trusted and who they merely used.
When the Security Service filed the records of Georg Hansen, a German operative arrested in London in 1927 and subsequently deported to the USSR, they placed him in the series for "SOVIET INTELLIGENCE AGENTS AND SUSPECTS" (KV 2/656). Hansen was an asset—a tool to be deployed and, if necessary, discarded.
Ulanovski, however, is listed in the "Personal (PF Series) Files. SOVIET INTELLIGENCE OFFICERS" (KV 2/1418). This is not a clerical detail; it is a statement of rank. An officer does not just steal secrets; an officer recruits, manages, and directs the agents. Ulanovski was a handler. He was the architect of the subversion, not the bricklayer.
This distinction explains the irony of his survival. While an agent like Hansen might be forgotten after a deportation, an officer is an investment. The Soviets spent years training Ulanovski in the nuances of pseudonyms and tradecraft. The fact that he survived the 1935 trials in Holland and Denmark without being permanently neutralized suggests that Moscow viewed his intellectual capital as more valuable than the embarrassment of his public exposure.
The American Gap
Following his legal disasters in Europe, Ulanovski did not retire to a dacha in the Soviet interior. Instead, he shifted his theater of operations to the USA, the North American federal republic where Soviet intelligence was aggressively expanding its reach during the 1930s.
The record states that "Later reports revealed he had also been active in the USA in the 1930s on behalf of Soviet Intelligence" (KV 2/1418). The phrasing "later reports revealed" is the most telling line in the file. It indicates that the Security Service did not necessarily track Ulanovski’s move to America in real-time; rather, they mapped his trajectory retrospectively.
This pattern points directly to the role of high-level defectors. The Security Service’s files include Igor Gouzenko, a Soviet Military Intelligence officer and cypher clerk who defected in Ottawa in 1945 (KV 2/1419). Gouzenko provided the West with a comprehensive map of Soviet networks that had operated in the shadows for decades. The "later reports" that placed Ulanovski in the United States bear the hallmarks of a Gouzenko-style disclosure: a retrospective forensic audit of a dead or dormant network, where names like "Nicholas Sherman" are finally linked to the man who was once tried for spying in Copenhagen and The Hague.
The Desk's Reading: The Professional Survivor
If this file is shaped the way it looks, the official summary is a mask for a much larger operation. The mention of "subversion worldwide" and Ulanovski's status as an "Officer" indicates that he managed a network of recruited assets whose names are conspicuously absent from this summary. The record tells us who the handler was, but it keeps the identities of the handled secret. The gap in the record is exactly the size of a Soviet sleeper cell.
The pattern suggests that Ulanovski was not a failure, despite the 1935 trials. In the world of professional intelligence, a public trial can be a useful cover—a way to "burn" an identity and emerge as someone else. The desk's reading is that Ulanovski used his legal troubles in Denmark and Holland as a pivot point, allowing him to vanish from European surveillance and resurface in the United States under a new set of pseudonyms.
Furthermore, the transition of Ulanovski’s activity from the 1920s to the 1930s suggests he was part of the pivot from the Comintern’s political agitation to the formal, state-sponsored espionage of the NKVD. He was a bridge between the revolution and the state.
The persistence of a Personal File for a man who had been publicly exposed in two countries proves that the Security Service viewed him as a lifelong threat. They didn't stop watching him because he was caught; they kept the file because they knew he was the type of man who could survive being caught.
What a full release of the PF Series would show is the specific list of American officials and diplomats Ulanovski compromised during his tenure in the USA. The current summary protects those legacies by focusing on the 1935 failures. The redacted pages likely contain the names of the people who helped Nicholas Sherman navigate the American corridors of power after the world thought he had been defeated in Europe. Ulanovski paid for his survival with the stability of the nations he infiltrated, and the Security Service, by maintaining this file, acknowledged that the Soviets had successfully weaponized his resilience.