Mathematicians or code breakers from what country were the first to break the codes in the Enigma machines used by the German military from the 1920s to the 1940s?
Japanese cryptology from the 1500s to Meiji the Polish military. Poland had fought the Soviet Union in 1920 and the Japanese believed the Poles would be receptive to the idea of teaching someone on the Soviet Union's opposite flank how to read Soviet codes. The Japanese Army could not have asked for more distinguished teachers. Polish cryptanalysts would later break early versions of the German Enigma machine in 1932 and their work jump-started the French and British efforts to break later, more complicated, Enigma machines. In the 1920s and 1930s it is accurate to say that Polish cryptanalysts were some of the best in the world. The
Japanese cryptology from the 1500s to Meiji machine systems breakable. So it is possible that the Japanese cryptanalysts knew that cipher machines were, in theory at least, breakable. The Polish military realized early on that machine enciphering would change the science of cryptology and from 1929 employed mathematicians to work on cryptanalysis. However, as the goal of Japanese-Polish cryptographic cooperation was to train the Japanese side to break Russian codes, there would have been no need for the Polish cryptologists to reveal methods of breaking machines the Russians were not using. Teaching the Japanese the latest and greatest methods would not be of any use against Russian