Enigma before Bletchley: the German spies who betrayed Hitler to steal codes

If I were to ask you to name the two men whose actions, above those of all others, decided the outcome of WW2, who would you name? Adolf Hitler and Winston Churchill, perhaps; or Dwight D Eisenhower and Herman Goering. How about if I added the condition that both these people were directly involved in breaking the codes of the Enigma Machine? Well, in that case you’d name Alan Turing of course, and Marian Rejewski.

Arguably, you would be correct. The latter, a Polish mathematician working for the Biuro Szyfrów (Cipher Bureau) was the first to open a breach in the ‘impenetrable’ cipher engine, reconstructing its internal wiring, while the former – quite rightly – has been widely credited with actually breaking the Enigma, solving its complex coding system and therefore giving the Allied nations a way to gain invaluable insight into the plans and operations of the German military.

As incredible as these feats of intellectual achievement were, they would not have been possible without the help of my own choice for the ‘top two’ game-changers of the Second World War. These men were not academics, nor were they politicians, nor were they even particularly likeable. They did, however, orchestrate a betrayal deep in the heart of Hitler’s circle of military advisers, stealing invaluable Enigma mechanical plans, keys and ciphers, as well as information on the movements and motivations of the fascists’ military forces. They were Rodolphe Lemoine and Hans Thilo-Schmidt.

My name is Lemoine, and I represent the French Intelligence Bureau. Tell me in detail who you are, what you do and why you are turning to us. I will listen… but first, would you like another glass of whisky?

Rodolphe Lemoine, aka Herr von Koenig, codename Rex, whose real name was Rudolf Stallmann, was an agent of the French Intelligence Bureau before and during the Second World War. His size and stature were hardly what one would associate with a spy: Rex was huge, both in height and girth, and this, coupled with his blunt speech and chequered past, made him a wholly intimidating individual. Though he was a German, Rex lived in Paris and went by a French variation of his wife’s name – Lemoine. He worked for the French Intelligence Bureau for approximately 20 years, despite having been previously expelled from France on suspicion of being a German spy, and during this time he became the main contact of our second game-changing German, Hans-Thilo Schmidt.

Schidmt, aka H.E. (Asché), unlike his recruiter, was not in the direct employment of the French Intelligence Bureau. He was more what you might call a freelancer, doing X amount of work for Y amount of payment, whenever it was available. His ‘real’ employment was as a civil servant at the German Armed Forces’ Cipher Office, a position obtained for him by his brother, General Rudolf Schmidt [who was at the time a lieutenant colonel], one of Hitler’s favourite generals.

H.E was responsible for the analysis of the decoded intelligence captured by the German military from intercepted messages in Western Europe – spying on the spies, as it were. This put him in a prime position to be of use to the Allied Forces, for Schmidt was no fan of the Nazi Party. So, when the Enigma machine was introduced for use in the German air force in 1933 (having been introduced to the German navy in 1926 and the German army in 1928), Schmidt wrote to the French Intelligence Bureau and offered to supply them with classified information about it. Leaping at the opportunity, the Bureau agreed, and put him in contact with Rex.

It was a long and fruitful relationship. Schmidt copied, memorised and stole vital plans and ‘keys’ (date-dependent code sheets used by those operating the Enigma) from the German Cipher Office, and exploited his brother’s position in the army to discover military plans and leak them to the French. Rex responded with envelopes full of cash and the promise of more to come – if H.E. could continue to deliver the goods, which he invariably did, much to the chagrin of the German Cipher Office.

Schmidt had reason to be jubilant. To intercept such intelligence represented quite a coup, but what satisfied him even more was the Abwehr’s inability to discover the origin of the leak

The Nazis smelled a rat. Or, more accurately, the Nazis smelled a rat, not realising the culprit was a mouse. Somehow, miraculously, Schmidt operated for years without detection and without suspicion. Investigations into the suspected espionage came up blank time and time again – after all, who would have suspected the outwardly average brother of one Hitler’s favourite generals?

For six long years, H.E. fed the Cipher Bureau the materials used to break the Enigma. While the French had little success interpreting or using the information on their own, their newly formed alliance with their Polish counterparts at the Biuro Szyfrów proved invaluable. With the stolen plans, the now-famous cryptographer Marian Rejewski was able to replicate the wiring within the rotors and reflector of the Enigma Machine, without ever having seen the original. Replicas of the machine were painstakingly produced, and one each sent to London and Paris.

On September 1, 1939, the war began. In London and Warsaw, and of course in Paris, the replica Enigma machines remained silent

But let’s be clear: the Enigma was not solved all at once. There was no sudden understanding, no light bulb illuminating, no triumphant shouts of ‘Eureka!’ echoing through the halls. It was slow, tedious and frustrating work. As soon as one code was solved it was replaced with a new one, and the message that had been deciphered was long past being useful.

When the Nazis invaded Poland in 1939, Rejewski and his colleagues we forced to flee to France, where they continued to work on the Enigma machine until the occupation of the country in June 1940, when he, along with the French Intelligence Bureau, was forced into hiding. Two years later, he fled to Britain.

Meanwhile, the men and women at Bletchley continued their agonising analyses and investigations. Both Rex and H.E. had fallen from the French Intelligence Bureau’s radar, having ceased to maintain regular communications with their employers. Yet still the information from H.E. came, and it was this that, step by step, piece by piece, led to the – shall we say ‘understanding’, rather than ‘breaking’? – of the Enigma machine by the inimitable Mr Turing.

In 1940, shortly after the battle of France, Hans-Thilo Schmidt fell silent. Rex had also disappeared, following his increasingly erratic and negligent behaviour (reports of unexplained absences, ill health, and apparently careless treatment of secret information occasionally reached the bureau). What happened next is another story, and is related in the first-ever English translation of Paul Paillole’s The Spy in Hitler’s Inner Circle, an eyewitness account of the Schmidt affair and the struggles of the French Intelligence Bureau in the 1930s and early 1940s.

What I find most remarkable about this book, besides retired agent Paillole’s endearingly stilted yet compelling narrative, is its demonstration of the endurance of the leaks. Wars are waged, countries are invaded, momentous decisions are made, yet all the while and without hesitation, H.E. continued to send a steady stream of state secrets to the enemies of his enemies, right under the nose of the Führer himself. Rex was no longer a young man, but reveled in the thrills of the whole operation, orchestrating the movement of secrets and assets across the continent with what often comes across, at least in Paillole’s account, as childlike enthusiasm.

Rex and H.E. may not have been similar in stature, attitude or outlook, nor did they have the same motivations for their actions, but one thing they did have in common was the love of their country – their Germany, whose future was threatened. Indeed, it was patriotism that led each man to his own shocking end – but I won’t spoil it for you. Suffice it to say, the Schmidt hit the fan.

“What a curious destiny for the Third Reich, whose police organisation spread terror throughout the continent, and was doomed to collapse by the actions of two of its very own citizens”.

Hannah McAdams is co-translator, with Curtis Key, of The Spy in Hitler’s Inner Circle. The book tells the story of Hans-Thilo Schmidt, France’s German spy embedded in the very heart of the Third Reich, whose intelligence helped to decode the Enigma machine

This article was first published by HistoryExtra in 2016