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Pre-1952 Historical Timeline

  • 1912 Nov 16 Herbert O. Yardley hired as Code Clerk, U.S. State Department
  • 1916 Colonel Parker Hitt, USA: published Manual for MilitaryCiphers
  • 1916 Jul 28 U.S. Navy Code and Signal Section established
  • 1917 Gilbert Vernam, AT&T, invented one-time tape teleprinter
  • 1917 Jan 16 Zimmermann Telegram sent
  • 1917 Mar 01 Zimmermann Telegram released to the U.S. press
  • 1917 Jun 10 Establishment of U.S. Army Code and Cipher Section, MI-8
  • 1917 Jun 29 Herbert O. Yardley commissioned First Lieutenant in U.S. Army
  • 1917 Jul 28 Captain Frank Moorman detailed to form U.S. Army Radio Intercept Section, AEF
  • 1917 Oct 29 First U.S. intercept in France in World War I
  • 1917 Dec 12 U.S. Army intercept station opened, Souilly, France
  • 1918 Apr 15 Arthur Scherbius offered prototype ENIGMA machine to German Navy
  • 1918 May William Friedman commissioned First Lieutenant, assigned to Radio Intelligence Section, France
  • 1919 May 19 Chief of the U.S. Department of State approved creation of Cipher Bureau (AKA Black Chamber)
  • 1919 Jul Agnes Driscoll employed by U.S. Navy
  • 1919 Oct 01 The Cipher Bureau began operations.
  • 1919 Nov 01 Great Britain: Government Code and Cipher School (GC&CS) established
  • 1920 William Friedman published The Index of Coincidence at Riverbank Laboratories
  • 1920 Dec 06 William Friedman hired as contract code compiler by U.S. Army
  • 1923 Chief of Naval Operations directed U.S. Navy to undertake intercept of foreign communications
  • 1924 U.S. established COMINT site in Shanghai
  • 1924 Jan 01 U.S. Navy established Radio Intelligence Office
  • 1924 Jan 01 Laurance Safford became Officer in Charge, Cryptographic Research, U.S. Navy.
  • 1924 Sep 30 Edward Hebern received a patent for a rotor-based electric code machine.
  • 1926 Feb 09 German Navy introduced the ENIGMA machine as "Radio Key C" for communications security
  • 1927 U.S. intercept station established, Peking
  • 1927 Swedish businessman Boris Hagelin introduced A-22 machine
  • 1928 U.S. Navy began Japanese kana intercept course
  • 1928 Jul 15 German Army introduced the ENIGMA machine for communications security
  • 1929 U.S. intercept station established, Guam
  • 1929 Mar U.S. intercept station in Shanghai decommissioned
  • 1929 May 10 U.S. Army decided to form Signal Intelligence Service; Friedman to be chief
  • 1929 Oct 31 The Cipher Bureau, headed by Herbert Yardley, closed
  • 1930 Apr 01 Frank B. Rowlett hired by William Friedman as cryptologist for U.S. Army Signal Intelligence Service
  • 1930 Apr 10 Abraham Sinkov hired by William Friedman as cryptologist for U.S. Army SIS
  • 1930 Apr 21 Solomon Kullback hired by William Friedman as cryptologist for U.S. Army SIS
  • 1930 May U.S. intercept station established, Olongapo, Philippines
  • 1930 May 13 John Hurt hired by William Friedman as Japanese linguist, U.S. Army SIS
  • 1931 Jan Intercept site established, Bar Harbor, Maine
  • 1931 Jun Herbert O. Yardley published The American Black Chamber
  • 1932 Mar Intercept site established, Astoria, Oregon
  • 1932 Dec Polish Cipher Bureau began deciphering German ENIGMA-based messages
  • 1935 Mar 11 U.S. Navy intercept reorganized and redesignated as OP-20-G
  • 1935 Apr U.S. Navy high frequency direction finding installed at Mare Island, California
  • 1935 Jul U.S. intercept site moved from Peking to Shanghai
  • 1937 Feb U.S. Army SIS produced first translation of Japanese diplomatic "RED" machine
  • 1937 Feb Great Britain: Air Ministry adopted TYPEX MK 1 cipher machine
  • 1938 Solomon Kullback published Statistical Methods in Cryptanalysis
  • 1938 Jun Japanese Ministry of Foreign Affairs introduced "PURPLE" cipher machine
  • 1939 Jan 01 U.S. Army Second Signal Service Company (later Battalion) created
  • 1939 Jun Japanese Navy introduced code system known to the U.S. as JN-25
  • 1939 Jul 24 UK-France-Poland tripartite meeting to discuss decryption of ENIGMA
  • 1939 Aug Astoria, Oregon intercept site relocated to Bainbridge Island, Washington
  • 1939 Sep U.S. Army SIS produced first translation of Japanese "PURPLE" machine
  • 1940 Aug U.S. Army approved exchange of cryptologic information with GC&CS
  • 1940 Sep 11 U.S. Army and Navy sign agreement on joint exploitation of Japanese "PURPLE" machine
  • 1940 Oct Cavite station moved to Corregidor
  • 1940 Oct Shanghai station decommissioned
  • 1941 Feb Sinkov-Currier mission to UK departed (in UK through Mar)
  • 1941 Mar Monitoring school established at Fort Monmouth
  • 1941 Jun 11 Herbert O. Yardley hired by Canada's National Research Council
  • 1941 Aug Commander Alistaire Denniston of GC&CS visited SIS
  • 1941 Sep DF station commission at Sitka, Alaska
  • 1941 Nov 22 Herbert O. Yardley dismissed by Canada's National Research Council
  • 1941 Dec 07 Japanese forces attack Pearl Harbor, Hawaii
  • 1942 U.S. Army Signal Intelligence Service redesignated Signal Security Service
  • 1942 U.S.-UK agreement on sharing naval communications intelligence
  • 1942 Jan First U.S.-Canada cryptologic exchange (captured French code)
  • 1942 Feb U.S. Navy Fleet Radio Unit, Melbourne (FRUMEL) established
  • 1942 Feb 01 German Navy introduced 4-rotor ENIGMA machine for U-boats
  • 1942 Feb 05 First evacuation of Station CAST (Corregidor) personnel
  • 1942 Mar 11 Second evacuation of Station CAST personnel
  • 1942 Mar 15 U.S. Navy began reading Japanese system JN-25
  • 1942 Apr 15 Central Bureau established in Australia to support Southwest Pacific operations
  • 1942 May DF station established at Kodiak, Alaska
  • 1942 Jun U.S. Army acquired Arlington Hall Station for the Signal Security Service
  • 1942 Jul Central Bureau moved to Brisbane
  • 1942 Jul Abraham Sinkov arrived at Central Bureau, Brisbane as Commander, 837th Detachment
  • 1942 Jul 08 FDR limits COMINT activities to Army, Navy, and FBI
  • 1942 Oct 05 U.S. Army SSA activated Vint Hill Farms
  • 1942 Nov COMINT station established on Guadalcanal
  • 1943 Feb 07 U.S. Navy OP-20-G moved to Nebraska Avenue
  • 1943 Mar German Navy adopted 4-rotor ENIGMA machine
  • 1943 Apr First break into Japanese Water Transport System
  • 1943 May GC&CS activated HEATH ROBINSON machine for cryptanalysis of German TUNNY machine
  • 1943 Aug Strategic intercept station at Amchitka, Alaska
  • 1943 Sep Intercept site established at Adak, Alaska
  • 1943 Dec Strategic DF station established at Tarawa
  • 1944 U.S. Army Air Corps established independent intercept operations
  • 1944 Feb Intercept and DF stations established at Kwajalein
  • 1944 Feb GC&CS activated COLOSSUS MK I for cryptanalysis of TUNNY; may be first computer
  • 1944 Apr 18 Army-Navy COMINT Coordinating Committee -- precursor of USIB -- first met
  • 1944 Nov DF station Tarawa decommissioned
  • 1944 Dec DF station Guadalcanal decommissioned
  • 1945 Feb DF station Amchitka decommissioned
  • 1945 Apr Intercept and DF stations established at Iwo Jima
  • 1945 Jul 03 Cryptographic Security Board established
  • 1945 Aug Strategic DF station established at Leyte
  • 1945 Sep 15 U.S. Army Signal Security Agency renamed Army Security Agency
  • 1948 Jun 23 Air Force Security Group activated
  • 1948 Oct 20 Air Force Security Group renamed Air Force Security Service
  • 1949 May 20 Armed Forces Security Agency established
  • 1952 Nov 04 National Security Agency established