Photo: Justin Tallis Agence France-Presse The information encryption machine used by the Nazis, called Enigma.
Jean-François Nadeau
Published at 0:00
- Europe
How to communicate within the army without being spotted and, above all, without being understood by the enemy ? At the time of the Normandy landings, the Allied intelligence services had for some time broken the codes of the famous machine to encrypt the information used by the Nazis. Called Enigma, a priori inviolable, this very sophisticated device rightly enjoyed, in its different variations, the full confidence of the German general staff. What could the Allies rely on for their part ? Historians claim that the war in Europe was shortened by about a year because the secrets of German communications had been cracked.
“The long sobs of the violins of autumn wound my heart with a monotonous languor”: this radio message, based on verses by Paul Verlaine, announces to the French Resistance that the hour of the landing has arrived. It’s simply a matter of being aware of the signal to understand it. But it is quite different for encrypted, cleverly coded messages.
Enigma
Talented mathematicians will devote themselves for months to cracking the German secrets of Enigma. They are gathered for this purpose in north London, at Bletchley Park, an estate which has now become a museum. There worked, under the direction of Alan Turing, those who broke the code of the German encryption machine. In fact, efforts to break German communications systems had begun well before that. As early as 1931, in Belgium, an agent double-curred part of Enigma's secrets. Part of the architecture of the machine will thus end up being known to the Polish intelligence services. Spanish republicans, thanks to good cryptographers, will also try to outwit the powerful German machine. The sharing of this information in France, then in England, will help to uncover its secrets. From then on, it is the course of the war that promises to be changed.
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The “bomb”
The work carried out on the Enigma machine by Alan Turing, a gifted mathematician, is today now well known. The life of this unusual scientist even earned him a bank note bearing his image, after his life was the subject, in the guise of the actor Benedict Cumberbatch, of a cinematographic adaptation (The Imitation Game). Turing's work, combined with that of other experts, ultimately made it possible to decode the Nazis' messages, by finding means whose foundations would later allow the invention of the computer. All this was put to the Allies' advantage, but the Russians were left out in this regard. Only fragmentary information was communicated to them, in the primary interest of Allied advances.
Using a device called “the bomb”, developed by Turing and his team, the Allied forces were able to decipher, at the time of the Normandy landings, a partial range of German army communications. However, in order not to reveal this decisive strategic advantage, it was decided to act as if nothing had happened. In order to prepare decisive action against the Nazi regime, the Allies did not use much of the decrypted information. This leads, on several occasions, to letting Nazi operations take place, even if it means sacrificing lives so as not to reveal their game.
This decisive breakthrough in information gave the Allies an advantage, but it did not protect Turing from the hunt that the state would unleash on him. On the grounds of his homosexuality, Turing was even forced to undergo chemical castration in the post-war period, following an improbable trial. The intelligence services then assumed that homosexuals were more likely than other citizens to betray their country. Turing would eventually commit suicide.
The secrets of indigenous languages
How did the Allies ensure that their communications were not intercepted and deciphered? ? All sorts of codes were used. However, it should be noted that the Canadian army, like the American army, will use indigenous operators to ensure its communications in complete security.
Many Indigenous soldiers served in the Canadian and American communications services during the Second World War. Indigenous languages were considered complex enough to be indecipherable to the enemy.
The last of these code talkers, Louis Levi Oakes of Akwesasne, died in 2019. As radio operators, many of them transmitted messages in their own language to another operator of the same nation as them. Their messages, it is still claimed today, could not be understood by the enemy.
Aboriginal people did not only occupy positions in communications. Among those who found themselves on the beaches of Normandy in June 1944 were Francis William Godon, George Horse and Tom Naphtahli Settee. But like them, the other Aboriginal people who wanted to enlist found themselves limited to the infantry, like the black soldiers. The navy and the Royal Canadian Air Force refused them, except in very rare exceptions motivated by special considerations. They served notably as snipers and scouts.
More than 4,000 Canadians of indigenous origin were enlisted during the war. Not counting the Métis, the Inuit and all those who were not recognized as such. In testimony, Canadian veteran Clarence Silver states: “When I served overseas, I was Canadian. When I came home, I was Indian. »
Le joual au front
It has been said that French Canadians, in the theater of operations, could communicate with each other in the popular language, in joual, in other words, in operations that involve radio transmissions. If this could have existed, it is not documented, argues Béatrice Richard, dean of education at the Royal Military College of Saint-Jean. “I haven’t heard of that, but indigenous operators have. »
For Stéphane Roussel, professor at the National School of Public Administration, “it’s logical and plausible.” Roussel has just published a book entitled The Second World War. Germans and Canadians face to face. He considers it reasonable to believe that the joual was used, without the need to be encrypted, in communications specific to radio exchanges between French Canadians. In 2004, he says, he accompanied a mission sent to observe Canadian soldiers based in Kandahar, Afghanistan. “I was part of a group that went to the 22nd Regiment in Afghanistan. At the command post, on the large screen which reported the exchanges between the units, we could see the conversations appear. There were codes for certain “sensitive” words. Some codes. But everything else was in Quebecois. In other words, everyone was certain that, even if intercepted, no one would be able to decipher these messages. »