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# NSA Historical Events

HomeHistoryCryptologic HistoryHistorical-Events

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                          - pre-1952 Timeline
                          - Pearl Harbor Review

# 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 

The Black Chamber

Navy Cryptology: The Early Days

The On-The-Roof Gang

Signal Intelligence Service

Early Japanese Systems

Linguists

COMINT Stations Overseas

Pearl Harbor Review - Following the Fleets

Army and Navy Get Their Act Together

JN-25

Red and Purple

The International Agreements

Pearl Harbor

The Investigations

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