Cipher Bureau (Poland)
The Cipher Bureau (Polish: Biuro Szyfrów, ) was the interwar Polish General Staff's Second Department's unit charged with SIGINT and both cryptography (the use of ciphers and codes) and cryptanalysis (the study of ciphers and codes, for the purpose of "breaking" them). The precursor of the agency that would become the Cipher Bureau was created in May 1919, during the Polish-Soviet War (1919–1921), and played a vital role in securing Poland's survival and victory in that war. In mid-1931, the Cipher Bureau was formed by the merger of pre-existing agencies. In December 1932, the Bureau began breaking Germany's Enigma ciphers. Over the next seven years, Polish cryptologists overcame the growing structural and operating complexities of the plugboard-equipped Enigma. The Bureau also broke Soviet cryptography. Five weeks before the outbreak of World War II, on 25 July 1939, in Warsaw, the Polish Cipher Bureau revealed its Enigma-decryption techniques and equipment to representatives of French and British military intelligence, which had been unable to make any headway against Enigma. This Polish intelligence-and-technology transfer would give the Allies an unprecedented advantage (Ultra) in their ultimately victorious prosecution of World War II. Background On 8 May 1919 Lt. Józef Serafin Stanslicki established a Polish Army "Cipher Section" (), precursor to the "Cipher Bureau" (). The Cipher Section reported to the Polish General Staff and contributed substantially to Poland's defense by Józef Piłsudski's forces during the Polish-Soviet War of 1919–1921, thereby helping preserve Poland's independence, recently regained in the wake of World War I. The Cipher Section's purview included both ciphers and codes. In Polish the term "cipher" () loosely refers to both these two principal categories of cryptography. (Compare the opposite practice in English, which loosely refers to both codes and ciphers as "codes".) During the Polish–Soviet War (1919–1921), approximately a hundred Russian ciphers were broken by a sizable cadre of Polish cryptologists who included army Lieutenant Jan Kowalewski and three world-famous professors of mathematics – Stefan Mazurkiewicz, Wacław Sierpiński, and Stanisław Leśniewski. Russian army staffs were still following the same disastrously ill-disciplined signals-security procedures as had Tsarist army staffs during World War I, to the decisive advantage of their German enemy. As a result, during the Polish-Soviet War the Polish military were regularly kept informed by Russian signals stations about the movements of Russian armies and their intentions and operational orders. The Soviet staffs, according to Polish Colonel Mieczysław Ścieżyński, In the crucial month of August 1920 alone, Polish cryptologists decrypted 410 signals: from Soviet General Mikhail Tukhachevsky, commander of the northern front from Leon Trotsky, Soviet commissar of war from commanders of armies, for example: the commander of the , the commander of the 1st Cavalry Army, Semyon Budionny the commander of the , Gai from the staffs of the XII, XV and XVI Armies from the staffs of: the Mozyr Group (named after the Belarusian city) the Zolochiv Group (after the Ukrainian town) the Yakir Group [after General Iona Emmanuilovich Yakir] from the 2, 4, 7, 10, 11, 12, 16, 17,