Hans Thilo-Schmidt
Hans Thilo-Schmidt was an employee at the German Army's cryptographic headquarters when, shortly after the Army version of the Enigma cypher machine was introduced, he decided to make some money. He contacted French intelligence and offered to supply information about the new machine. His offer was accepted by its chief, M Bertrand, and he was given the code name Asch by the French.For the next several years, until he left his position in Germany, he met with French agents at various sites throughout Europe and supplied copies of the instruction manual for the machine, operating procedures, and key schedules. Even with this information, French intelligence was unable to break messages protected by the German Army's Enigma machine.
The French shared some of the intelligence take from Asch with the Polish cryptographic Bureau, and starting in 1932, the Poles began to read some of the Enigma traffic. They got better at it as they gained experience and insight, and by the late 1930's were reading a substantial portion of the traffic they were able to intercept. Incredibly, the most credible sources suggest that the initial break into Enigma, made by Marian Rejewski, was not aided by Asch's material. It had been withheld from him by his supervisor!
Asch was eventually uncovered as a French spy by the Gestapo after the Fall of France when the French agent who had been his 'control' was captured and made a deal.
It seems, based on his daughter's account, that he was not executed by the Germans.
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