The Cipher Bureau
During the Polish-Soviet War, in 1919, Poland formed its first intelligence agency, the precursor of the Biuro Szyfrow or Cipher Bureau. In 1931, the Cipher Bureau was formed by merging several smaller agencies to create a single agency devoted to cryptology. The Cipher Bureau was responsible various code-related tasks, including cryptography and cryptanalysis.
Even in the early years, the Polish Cipher Bureau was fast, efficient and well-organized. Messages were typically decrypted within a day, and passed directly to military intelligence, and key members of the military, including the Chief of General Staff. The Cipher Bureau provided essential intelligence about Soviet activities and military operations during its early years.
Around the end of 1927 or early 1928, Polish authorities intercepted a German package, containing an early, commercial-issued Enigma machine. This sparked interest in Enigma, and provided an idea of the basis for Enigma. The Enigma machine was an electro-mechanical rotor cipher machine, invented in Germany around the end of World War I.
Work on Germany’s Enigma cipher began in 1932. Over the next seven years, Polish cryptographers worked to break and decode Enigma. Between 1932 and 1938, Poland developed a number of different tools, including the bombas, to decode Enigma; however, the Germans responded by making the Enigma machines more complex and the codes harder to decipher. In July 1939, Polish cryptographers provided French and British intelligence with the information they had available on Enigma to assist Allied intelligence efforts. The invasion of Poland and the official beginning of World War II came just over a month later, on the first of September 1939.
The Polish expected the invasion; they were already effectively translated German messages and were aware of, in 1939, approximately 95 percent of the German order of battle. Their knowledge of the expected invasion, and their understanding of what was likely to come enabled them to share their knowledge while they were still able to do so. The Cipher’s Bureau’s advances in cryptanalysis provided the basis for Allied intelligence effort.