Breaking German codes real reason for 1942 Dieppe raid: historian

Members of the Royal Canadian Medical Corps evacuating Allied soldiers from the beach after the Dieppe, France raid during the Second World War. The Associated Press

Originally published August 9, 2012

TORONTO – New research suggests the real intent of the historic raid on Dieppe in 1942 was to steal a machine that would help crack top-secret German codes.

Military historian David O’Keefe spent 15 years searching through the once-classified and ultra-secret war files and says the real purpose behind the Dieppe operation-which cost hundreds of Canadian soldiers their lives – was to capture advanced coding technology from the German headquarters near the French beach.

“For years, so many veterans, men who stormed the beaches and ended up in prisoners of war camps, had no clue what the reason was that they were there,” O’Keefe tells Global National’s Christina Stevens.

“They had their own missions, but they did not understand what the driving force was behind the raid.”

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Historians have assigned many purposes to the disastrous raid: to gather intelligence from prisoners and captured materials, to assess Germany’s response to amphibious raids, to boost Allied morale and to assure the Soviets-locked in a titanic struggle with Germany – that the west was committed to fighting in Europe.

On August 19, 1942, an Allied force of 300 ships, 800 aircraft, and 6,000 assault troops launched a one-day attack known as Operation Jubilee on the French port of Dieppe.


Breaking German codes real reason for 1942 Dieppe raid: historian - image
Michael Bergeron , Shaw Media

Two minor beaches on the flanks – Puys and Pourville – were to be captured, while an attack 30 minutes later was scheduled on the main beach by two Canadian infantry battalions, the Essex Scottish Regiment and the Royal Hamilton Light Infantry.

Of the 5,000 Canadians who landed at Dieppe, 907 were killed, 586 wounded and about 2,000 were taken prisoner.

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“When you look back at it, war is horrible,” Ron Beal of the Royal Regiment of Canada tells Global National.

Beal was an infantryman when he landed on Blue Beach 70 years ago. “It is absolute hell and we prayed that it would never happen again.”

Decoding Dieppe
Bletchley Park, located just north of London, was the centre of British code-breaking in the Second World War. Scientists and mathematicians would intercept and crack enemy radio messages by breaking into ciphers and codes used to keep top-secret information private.

For the Allies, the Bletchley Park operation was crucial to move supplies and win the Battle of the Atlantic.

According to O’Keefe’s research, British naval officers used Operation Jubilee to target the German-made Enigma code machine, an electro-mechanical piece of equipment that used a series of rotors for the encryption and decryption of secret messages.

Unlocking such a device, says O’Keefe, would mean knowing enemy intentions – information that could potentially reveal German intent, capabilities, hopes, and fears.

“It’s like reading your opposition’s e-mail or, better yet, reading your opposition’s poker hand and knowing exactly how to play or use your forces,” says O’Keefe. “The Allies relied on this in almost every decision they made in the Second World War.”

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While the British were successful breaking into the three-rotor Enigma machines, everything changed on February 1, 1942, when the Germans introduced the four-rotor Enigma device – instantly blacking out Bletchley Park.

According to files, British naval intelligence believed that in order to crack the four-rotor Enigma machine, a pinch raid was necessary. A successful pinch would mean secretly stealing parts of the machine, code books and setting sheets.

Ian Fleming and the 30 Assault Unit

During the Second World War, Ian Fleming – the legendary author of the James Bond spy series novels – acted as a personal assistant to Britain’s head of naval intelligence, Admiral John Godfrey.

He, along with other naval intelligence specialists, created the No. 30 Commando or the 30 Assault Unit (30AU) – a team of special commandos that were put into the Dieppe operation under the unit name No. 40 Royal Marine Commando.

According to the newly-discovered files, while Fleming and the 30 AU were looking to hit various German vessels that were in Dieppe’s harbour, their primary target was the German headquarters, located at Hotel Moderne near the main harbour in Dieppe.

The main target
A search plan revealed that British naval intelligence considered Hotel Moderne to be the German naval headquarters and control centre. They believed the hotel room would house Enigma coding machines and a safe with enough material regarding German war operations for the next six to eight months.

On August 18th, the 30AU was put on the British ship HMS Locust, whose mission was to breach the inner channel and deliver the Royal Marine Commando into port. Despite several attempts to reach the harbour, the unit was later sent in on landing craft that also failed to reach the main beach.

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Meanwhile, Fleming was located on the destroyer HMS Fernie with instructions to return to British port with any material the 30 AU unit obtained. No pinched material reached HMS Fernie and Fleming and the ship returned to Britain empty-handed.

Had the pinch raid been successful, Beal believes it would have had a substantial effect on the war.

“There are families out there that think their sons died for nothing,” says Beal.”Now they’ll know there was a real purpose and that purpose could’ve shortened the war.”

Several months after the failed operation in Dieppe, the minds at Bletchley Park broke the code of the four-rotor Enigma machine.

“We can never look at Dieppe the same way,” says O’Keefe. “But now we know that there was somewhat a silver lining to Canada’s darkest day.”


 History Television will air the full documentary Dieppe Uncovered on Sunday, August 19 at 9:00 PM ET/PT.

– With files from Global National’s Christina Stevens

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