Operation Fortitude was the code name for the plan to deceive and divide the Nazis in the build-up to D-Day, the 1944 Allies’ invasion of German-occupied France.
Operation Fortitude’s spies were an oddball mix of operatives working for Britain - a convicted safecracker, a Spanish chicken farmer, and a French woman who was so obsessed with her dog Babs that she almost derailed the D-Day invasion. Added to that was a fake ‘ghost’ Army created to mislead the Germans about Allied troop movements which was led by American General George S. Patton.
Operation Fortitude’s spies had a few equally unlikely handlers at British intelligence agency MI5 as well, including Thomas Argyll ‘Tar’ Robertson, known around the office as ‘Passion Pants’ because of his penchant for wearing his regimental tartan trousers.
Tar was head of B1A, the spy section that ran the British-German double agents. He also helped set up the Twenty (XX) Committee in 1941 - known as Double Cross - an inter-agency group to coordinate spies working both for the British secret services and the Abwehr, the German military intelligence service.
At the center of it all was Nathalie ‘Lily’ Sergueiew - ironically codenamed ‘Treasure’ because she was a nightmare to deal with - and her Jack Russell, ‘Babs’.
Mercurial French spy Lily Sergueiew with Babs (aka Frisson)
The D-Day Misfits & Babs
Lily, a French woman of Russian extraction, was educated in Paris, trained as a journalist, and spoke fluent English, French, and German which gave her an excellent cover story and grounding in spycraft. Lily had traveled extensively throughout Germany in the ‘30s, once interviewing Hermann Göring, a veteran WWI fighter pilot ace and a powerful politician in the Nazi Party that ruled Germany from 1933 to 1945.
The Nazis tried to recruit Lily for the German intelligence service but she initially refused, relenting only after the Germans occupied her beloved France. The other love of Lily’s life was her dog ‘Babs’ - aka Frisson. Unfortunately, Babs was forced into quarantine during the war, stuck in Gibraltar and unable to travel freely around Europe with Lily.
With her German intelligence job secured, Lily went to Madrid where she knocked on the door of the British Embassy and volunteered to become a double agent. Her new role involved travel between the UK and neutral Portugal, feeding disinformation to her German handlers and later deceiving the Nazis about the location of the D-Day landings. Lily was increasingly concerned about the fate of Babs, however, threatening to ‘strike’ unless British operatives freed Babs.
“Treasure is very upset about the absence of [her] dog and has seriously threatened that if the dog does not arrive soon she will not work any more,” Lily’s MI5 case officer, Mary Sherer, warned in December 1943. "I am afraid Treasure's American boyfriend has let her down and has no intention of smuggling the dog over here for her. I am wondering whether we could get the Navy to help.”
When Lily eventually discovered Babs was dead, she accused the British of ‘murder’. Her UK handlers worried that Lily may be unhinged and intent on revenge. Would Lily tell the Germans the truth about the planned D-Day invasion?
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Operation Fortitude was the code name for the plan to deceive and divide the Nazis in the build-up to D-Day, the 1944 Allies’ invasion of German-occupied France.
Operation Fortitude’s spies were an oddball mix of operatives working for Britain - a convicted safecracker, a Spanish chicken farmer, and a French woman who was so obsessed with her dog Babs that she almost derailed the D-Day invasion. Added to that was a fake ‘ghost’ Army created to mislead the Germans about Allied troop movements which was led by American General George S. Patton.
Operation Fortitude’s spies had a few equally unlikely handlers at British intelligence agency MI5 as well, including Thomas Argyll ‘Tar’ Robertson, known around the office as ‘Passion Pants’ because of his penchant for wearing his regimental tartan trousers.
Tar was head of B1A, the spy section that ran the British-German double agents. He also helped set up the Twenty (XX) Committee in 1941 - known as Double Cross - an inter-agency group to coordinate spies working both for the British secret services and the Abwehr, the German military intelligence service.
At the center of it all was Nathalie ‘Lily’ Sergueiew - ironically codenamed ‘Treasure’ because she was a nightmare to deal with - and her Jack Russell, ‘Babs’.
Mercurial French spy Lily Sergueiew with Babs (aka Frisson)
The D-Day Misfits & Babs
Lily, a French woman of Russian extraction, was educated in Paris, trained as a journalist, and spoke fluent English, French, and German which gave her an excellent cover story and grounding in spycraft. Lily had traveled extensively throughout Germany in the ‘30s, once interviewing Hermann Göring, a veteran WWI fighter pilot ace and a powerful politician in the Nazi Party that ruled Germany from 1933 to 1945.
The Nazis tried to recruit Lily for the German intelligence service but she initially refused, relenting only after the Germans occupied her beloved France. The other love of Lily’s life was her dog ‘Babs’ - aka Frisson. Unfortunately, Babs was forced into quarantine during the war, stuck in Gibraltar and unable to travel freely around Europe with Lily.
With her German intelligence job secured, Lily went to Madrid where she knocked on the door of the British Embassy and volunteered to become a double agent. Her new role involved travel between the UK and neutral Portugal, feeding disinformation to her German handlers and later deceiving the Nazis about the location of the D-Day landings. Lily was increasingly concerned about the fate of Babs, however, threatening to ‘strike’ unless British operatives freed Babs.
“Treasure is very upset about the absence of [her] dog and has seriously threatened that if the dog does not arrive soon she will not work any more,” Lily’s MI5 case officer, Mary Sherer, warned in December 1943. "I am afraid Treasure's American boyfriend has let her down and has no intention of smuggling the dog over here for her. I am wondering whether we could get the Navy to help.”
When Lily eventually discovered Babs was dead, she accused the British of ‘murder’. Her UK handlers worried that Lily may be unhinged and intent on revenge. Would Lily tell the Germans the truth about the planned D-Day invasion?
In addition to Lily and Babs, MI5 was also preoccupied with capturing German agents who parachuted into Britain to spy for the Nazis. Britain’s Government Code and Cypher School (later known as GCHQ) had managed to break the German Enigma codes with the help of math genius Alan Turing. The Brits were lucky in that Germany sent many poorly trained - and sometimes reluctant spies - to the UK who happily turned against Germany and worked as double agents for Britain once captured.
Among them was convicted criminal Eddie Chapman, codenamed ‘Zigzag’, a safecracker imprisoned in Guernsey when it was occupied by the Germans. The Abwehr recruited Chapman, trained him in spycraft, and parachuted him into England where he surrendered to MI5. Chapman continued to impress his German case officer, however, ultimately awarded the Iron Cross while working as a double agent for Britain.
Another of Operation Fortitude’s eccentrics was Peruvian Elvira Chaudoir, codenamed ‘Bronx’ after a popular cocktail. She was the daughter of a diplomat who made his fortune in bird and bat excrement. Elvira grew up in Paris and enjoyed the excitement of Europe’s casinos. Recruited by Claude Dansey, deputy chief of Britain’s Secret Service, MI6, she too delighted in feeding misinformation about Allied troops to the Abwehr.
Playboy Dusan ‘Dusko’ Popov, codenamed ‘Tricycle' - possibly because he was a triple spy, or because he was often involved with at least two women - was a lawyer who also loved gambling and fast cars. Dusko reportedly warned the US about Pearl Harbor. Was he also the model for James Bond? Popov thought so and spread the rumor far and wide.
The fifth misfit was Spanish anti-Fascist Juan Pujol Garcia, codenamed ‘Garbo’, a graduate of a prestigious Spanish chicken farming school. Juan approached both the British and Germans hoping to become a double agent for the Allies. He had a talent for deception. By 1944, Juan supposedly ran a network of 26 agents supplying intel (and disinformation) to the Germans.
A reconstructed station beneath Dover Castle where fake radio messages were relayed
The D-Day invasion
The key to the Operation Fortitude disinformation campaign - part of a wider plan codenamed Bodyguard - was to make the German government believe British and Allied forces would invade France using the sea crossing from Dover, England to the Pas-de-Calais, France. In fact, the real invasion would fall in Normandy on June 6, 1944.
Britain and the US even created a fake Army - the First United States Army Group (FUSAG) - stationed in south-east England under General Patton to give the impression it was mobilizing for a Pas-de-Calais invasion. Patton, the senior American field commander, was picked to reinforce the idea that he was leading a major assault. Dummy tanks were also deployed across southeast England. Canadian and British forces sent fake radio (signals) messages using false information to further mislead the Germans.
To make the operation even more complex, Operation Fortitude was split into two contradictory deceptions: Fortitude North made it appear as though the Allies were using Scotland to invade Norway; Fortitude South made it appear that the Allies would invade France at the Pas-de-Calais rather than Normandy.
Lily ‘Treasure’ Sergueiew
Lily ‘Treasure’ Sergueiew
With the help of the Operation Fortitude spies, the Allies duped German intelligence on D-Day and delayed the movement of key German military units on the battlefield until a month after Allied forces had secured five beaches and moved inland from Normandy.
As for Lily ‘Treasure’ Sergueiew, she’d informed MI5 that she had a prearranged secret signal to alert the Germans if she was under British control. Lily threatened to use it in 1944 as revenge for her dog’s death which could derail the D-Day invasion and all of the painstaking planning that had gone into the deception operation. After a tumultuous meeting with Colonel ‘Passion Pants’ Robertson, Lily revealed her secret code and continued to work for MI5, sending the Germans false information until a week after D-Day when Lily was effectively fired.
Sergueiew returned to France initially and later emigrated to the US and where she died in 1950. Lily’s memoir, Secret Service Rendered, was published in 1968. In it, she describes some of her MI5 colleagues as ‘gangsters’.
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