Constance Babington Smith photographically interpreted Hitler’s secret weapon: an object less than a millimetre long on an aerial photograph.

This is the true story of how her team at RAF Medmenham uncovered the V-1 and V-2 rockets, severely disrupting Axis operations:
(🧵) Intelligence on Hitler’s secret weapons programme became one of the most urgent priorities of the war. The threat posed by the V-1 and V-2 rockets to London and the rest of Britain was grave. Had they not been disrupted, they could have cost the Allies victory.

After bugged conversations at Trent Park confirmed the existence of the V-weapons programme, the RAF flew fresh sorties over the secret experimental site at Peenemünde.

Previous photographs had not allowed RAF Medmenham to identify the site with certainty. By late spring 1943, however, Peenemünde was clearly labelled as Hitler’s secret experimental station. This led directly to the heavy bombing raid on the night of 16/17 August 1943.

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In the 1930s, Friedl Gärtner, an Austrian agent working for British Intelligence, infiltrated Nazi networks in the United Kingdom, successfully navigating a perilous landscape of double-cross and deception.

This is her remarkable story:
(🧵) Friedl Gärtner, born Friedl Stottinger in Austria, was a strikingly beautiful stenographer in 1930s Vienna, fitting the post-Mata Hari archetype of the female spy.

She married an Orthodox German Jew (his name redacted in MI5 files) and emigrated with him to Palestine, but the marriage ended in divorce. With only her ailing mother left in Austria, Gärtner moved to Britain in April 1938, shortly after Hitler’s annexation of Austria.

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Curt Ascher was one of Hitler’s few serious political opponents during the 1930s.

On 2 October 1937, Curt was taken to Dachau concentration camp.

This is that tragic story:
(🧵) On 2 October 1937, Curt was taken to Dachau concentration camp, a little over five miles north-west of Munich.

His name is listed in the camp Zugangsbücher (intake books) as prisoner number 12792. These books are now held at the National Archives and Records Administration in Washington, DC.

The entry shows that he was born on 12 December 1882 in Glatz–Oberschlesien and imprisoned in Dachau on 2 October 1937.

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Jane Sissmore, MI5’s first female officer, led its Soviet espionage unit by 1929.

Her MI6 career was derailed when double agent Kim Philby sidelined her, fearing she would expose his treachery.

Let's explore:
(🧵) Kathleen Jane Sissmore, later Mrs Archer, joined MI5 as a clerk in 1916 at 18, rising swiftly due to her determination.

Described as ‘a strong character, very straight, well-principled, industrious’ by her headteacher, she trained as a barrister while working full-time.

Her organisational skills earned her an MBE in 1923, and by 1924, she was called to the Bar.

In 1928, she became controller of MI5’s Registry, a remarkable feat in a male-dominated field.

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At only 19 years old, Joan Miller went from an ordinary typist job to being recruited as a spy by MI5 in 1939 to infiltrate the Right Club.

From Wormwood Scrubs’ grim cells to Blenheim Palace, she outsmarted fascists by posing as one of their own.

This is her story:
(🧵) Nineteen-year-old Joan Miller, from an affluent background, faced a challenging childhood with socialite parents who gambled away their wealth and later divorced.

Raised by nannies and educated at boarding school, she spent holidays with relatives. After school, she worked as a typist at Elizabeth Arden, rising to the advertising department.

Recruited to MI5 in 1939 by school friend Janet Withers, Miller joined the Registry, tracking subversive individuals and groups.

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Countess Yvonne de la Rochefoucauld worked for SOE’s F Section during WW2.

She and her husband were both arrested—he died in a Nazi prison camp, while she survived brutal torture.

She was awarded Britain’s King’s Medal for Courage.

This is her remarkable wartime story:
(🧵) Countess Yvonne de la Rochefoucauld was a French civilian working for SOE’s F Section.

In 1940, while serving in a French hospital, she was arrested and imprisoned by the Germans.

Released the following year, she immediately joined the resistance in Normandy—using her skills as a doctor to treat many wounded airmen near her home.

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In 1938, a rogue pilot, his girlfriend, and a hidden camera flew over Nazi Germany—and changed spycraft forever.

Their images, taken from a hangar near London, laid the foundation for modern intelligence.

This is the story of Sidney Cotton:
(🧵) In 1938, MI6 recruited Sidney Cotton to pioneer aerial reconnaissance of Germany’s rearmament.

He set up his fledgling unit in a hangar at Heston Airfield, west of London.

His girlfriend, Pat Martin (pictured), a skilled photographer, joined him on covert flights over Germany, capturing images of military sites critical to British intelligence.

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Operation Valkyrie was the 1944 plot to assassinate Hitler with a bomb hidden inside a briefcase.

Agent Rita Winsor and defector Otto John met in Lisbon's shadowy streets at night to plan the attack.

The attempt was unsuccessful.

Here's what happened:
(🧵) New information in declassified files sheds light on one particular complex MI6 operation from Lisbon that involved Rita Winsor, the defector Otto John (an MI6 asset) and the plot to assassinate Hitler in July 1944.

Otto John, a lawyer working for the German airline Lufthansa, used his position to fly to Lisbon and elsewhere, to meet his British handlers Rita Winsor and Graham Maingot, without suspicion.

Codenamed Whiskey, Otto John had already met twelve times with them in the two years leading up to Operation Valkyrie.

He is believed to have acted as an intermediary between the German resistance chief Colonel Georg Hansen and MI6.

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Wolfgang Likwornik was a Jewish refugee who fled Nazi Austria to join the British Army’s Gordon Highlanders.

Landing in Normandy in 1944, he fought through fierce battles, interrogated POWs, and survived the war, only to erase his past by defacing his own name years later:
(🧵) Born into an assimilated Viennese Jewish family in 1924, Wolfgang Likwornik escaped Austria sometime after the Anschluss to join his aunt and uncle in France.

From there he came to Britain in May 1939 and found work as an apprentice printer in Glasgow. In the summer of 1940 he was interned. In December 1943 he enlisted in the British Forces and was sent to Maryhill, near Glasgow for infantry training.

His army records show that he may have been under military age when he volunteered because the words ‘age limit to be waived as a special case’ appear on one of the official forms.

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Was Admiral Canaris, head of the German Secret Service, an Allied double agent in WW2?

Declassified files reveal MI6’s secret plot to ‘turn’ him!

It's thought that Canaris was asked to open the Atlantic Wall to Allied forces for an invasion...

Let's explore:
(🧵) Over the decades there has been speculation as to whether Admiral Canaris, head of the German Secret Service, was working secretly for the Allies.

Declassified material may answer this question to a pretty reliable degree as it is clear that MI6 had been tracking Admiral Canaris since at least 1936.

One of the main targets by British intelligence in the 1940s was to surreptitiously destroy the German intelligence service without the Nazi regime even realising.

One way to do that was to ‘turn’ Canaris to work for the Allies.

Towards the end of 1940, Guy Liddell (head of counter-espionage at MI5) suggested to Valentine Vivian of MI6 that ‘we ought to try and get at Admiral Canaris.’

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In WW2, breaking the enemy's codes was the highest priority.

Enter Bletchley Park - a secret estate bought with £6,000 of private funds to crack the "unbreakable" German Enigma codes.

Margaret Godfrey was one of the very first women at "the park."

This is the story:
(🧵) The highest priority in wartime is to break the enemy's codes and ciphers; and in the case of the Second World War, the various German enigma codes.

A special site was therefore required outside of London to crack the various encrypted messages between the different German services and the High Command, as well as between Hitler and his Secret Service (Abwehr).

In the 1920s-30s, MI5’s female agents outwitted communist and fascist spies threatening Britain.

From foiling Moscow’s plots to infiltrating Oswald Mosley’s British Union of Fascists, their daring coups rewrote intelligence history:
(🧵) In the 1920s and 1930s, Britain faced dual threats from Comintern’s communist spies infiltrating via the Communist Party of Great Britain and the fascist British Union of Fascists (BUF), led by Sir Oswald Mosley.

The BUF’s anti-Semitic, nationalist rallies, notably the violent Battle of Cable Street in London’s East End on 4 October 1936, saw clashes with Jewish communities and workers, highlighting the escalating tensions.

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In the 1960s, Herman Rothman recognised a name on a list of accused Auschwitz war criminals.

It was someone he once knew.

He had Perry Broad's diary in his attic.

What happened next took him to the courtroom of one of the most infamous Nazi trials in history:
(🧵) This is that story, told by Herman Rothman:

In the late 1950s in a cellar in Munich, a hoard of documents was discovered and the name of Perry Broad surprisingly appeared in the newspapers. Alarm bells rang but I temporarily filed the information, but it was to re-surface some ten years later. I was about to cross paths with Perry Broad again.

In the early 1960s I heard on the radio and read in the newspapers of the arrest of twenty-two people accused of war crimes in Auschwitz. As I scanned the list I found Perry Broad’s name amongst them. The copy of his diary which I had amongst my own papers in my attic immediately came to mind.

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In her youth, Joan Stafford King-Harman idolised Hitler—but everything changed when MI6's Director of Naval Intelligence recruited her. She became one of the service's first female desk officers.

How did a Nazi admirer flip to become a key British spy?

Let's explore:
(🧵) Joan Stafford King-Harman, who later became Lady Dunn, broke new ground as one of the earliest female desk officers at MI6, pioneering a vital intelligence role.

Born to Sir Cecil Stafford-King-Harman, the 2nd Baronet of Rockingham in Ireland, she was scouted and hired by John Godfrey—then Director of Naval Intelligence—to serve as a secretary in MI6's naval division, thanks to her strong proficiency in German.

The opportunity arose during a Scottish getaway with friends, when Godfrey casually asked if they could recommend any young women adept at typing and sworn to utmost secrecy.

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5 Cocktails favoured by Allied Intelligence Services during the First and Second World Wars

Next time you're at a bar, why not order one of these and raise a glass to the courageous heroes and heroines of that era:
(🧵) 1. Pink Gin

The preferred cocktail of British Naval Intelligence interrogators during the Second World War was Pink Gin.

Pictured here at the covert WWII listening site Latimer House, including Ian Fleming (author of the James Bond spy novels):

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In 1938, MI6 chief Hugh Sinclair bought Bletchley Park, believing intelligence would win the war.

By D-Day, 7,800+ codebreakers and MI9’s 'Secret Listeners' at Trent Park uncovered Nazi secrets, from V-1 sites to SS units, shaping Allied victory.

Let's explore:
(🧵) It was the 1st Duke of Marlborough (1715) who once said: ‘No war can be conducted successfully without early and good intelligence.’

That was also the belief of Hugh ‘Quex’ Sinclair (the head of MI6) in 1938 as Britain faced the escalating threat of war from Nazi Germany.

Sinclair believed whoever would win the intelligence game would win the war – and with that in mind, he purchased Bletchley Park in Buckinghamshire and moved the Government Code & Cipher School (GC&CS) out there from Broadways Buildings (then MI6 HQ in London).

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In 1940, MI9 turned London’s lavish Kensington mansions into the chilling "London Cage," a secret interrogation centre where truth drugs & intense tactics were used on Nazi prisoners.

Declassified files expose a dark, untold chapter of history:
(🧵) In autumn 1940 British intelligence, MI9, opened a secret interrogation centre in the heart of the millionaire enclave of London’s Kensington Palace Gardens.

Taking over Nos. 6-7 and 8 & 8a, its commanding officer Colonel Alexander Scotland ensured that the mansion houses were stripped off their former luxury and the ‘cage’ was established as a grim prison.

It soon developed a formidable reputation in military circles for any prisoner of war transferred there for interrogation.

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The recent passing of Betty Webb MBE, a codebreaker at Bletchley Park during the Second World War, reminds us of the extraordinary role played by female intelligence analysts in the defeat of Nazi Germany.

This is my tribute thread to her:
(🧵) At the age of 101, Betty Webb could still be seen at the wheel of her car, driving around the small village where she lived in Worcestershire, in the English Midlands.

In retirement she was spritely and active in education, giving talks to over 200 schools and travelling abroad to speak to groups on her wartime career.

When asked about her war years, she once said, ‘I wanted to do something more for the war effort than bake sausage rolls.’

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Stephen Dale (Heinz Günther Spanglet), a survivor of Nazi concentration camps, later parachuted into enemy territory with the SOE.

Captured by the SS, he faced execution.

What happened next will leave you speechless:
(🧵) Stephen Dale (Heinz Günther Spanglet), born in Berlin and a survivor of Sachsenhausen concentration camp, arrived in England in spring 1939, taking various jobs to support himself.

Interned in Australia in 1941, he later joined the Pioneer Corps with 87 Company. In 1943, he transferred to the SOE and commenced training.

In June 1944, he flew to Gibraltar, joining three others for their mission, then proceeded to a rudimentary camp in Algiers before reaching Fasano on Italy’s Adriatic coast. Before parachuting, he adopted the name Stephen Patrick Turner.

(continued)

As British Forces advanced beyond Bayeux, Harry Rossney faced the sombre task of burying thousands of fallen Allied soldiers in Normandy.

He painted war cemetery signboards and carved inscriptions on countless graves, a stark reflection of his duties:
(🧵) Harry Rossney, a sign-writer by trade, transferred from 93 Company of the Alien Pioneer Corps to 32 Graves Registration Unit in Bayeux, where the brutal realities of war were constant.

He supervised and trained workers to create temporary grave markers, later replaced by white stones from the Imperial War Graves Commission (now Commonwealth War Graves Commission).

Rossney also hand-painted large signboards for war cemeteries across Normandy, including Bayeux, Ranville, and Hottot.

(continued)

He was not a British traitor!

Fresh evidence exonerates MI6’s Charles Howard Ellis from betraying Spymaster Thomas Kendrick in 1938, unmasking a real double agent elsewhere in the network...

Discover the real role Ellis played in British intelligence history:
(🧵) On 17 August 1938, Thomas Joseph Kendrick, Britain’s foremost spy in Europe with nearly three decades in the Secret Intelligence Service (SIS/MI6), was apprehended by the Gestapo while attempting to cross the Austrian border to safety—a calamitous blow to MI6 in its first 30 years.

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