The Black Chamber, otherwise known as MI-8, was America's first peacetime cryptanalytic organization and a forerunner of the top-secret National Security Agency. The only prior codes and cypher organizations maintained by the US govenrnment had been some intermittent, and always abandoned, attempts by Armed Forces branches prior to WWI. This article is about the country in North America. ... Cryptanalysis (from the Greek kryptós, hidden, and analýein, to loosen or to untie) is the study of methods for obtaining the meaning of encrypted information without access to the secret information which is normally required to do so. ... NSA seal The National Security Agency / Central Security Service (NSA/CSS) is believed to be the largest United States government intelligence agency[citation needed]. It is responsible for the collection and analysis of foreign communications and for the security of U.S. government communications against similar agencies elsewhere. ...

Headed by Herbert O. Yardley (1889 - 1958), it was founded immediately following World War I. Jointly funded by the Army and the State Department, MI-8 was disguised as a New York City commercial code company; it actually produced and sold such codes for business use. Its actual mission, however, was to break the communications (chiefly diplomatic) of other nations. Its most notable known success was during the Washington Naval Conference during which it aided American negotiators considerably by providing them with the decrypted traffic of many of the Conference delegations, most notably the Japanese. Herbert Osborne Yardley (13 April 1889-7 August 1958) was an American cryptologist most known for his book The American Black Chamber (1931). ... 1889 (MDCCCLXXXIX) was a common year starting on Tuesday (see link for calendar). ... 1958 (MCMLVIII) was a common year starting on Wednesday of the Gregorian calendar. ... Combatants Allied Powers: British Empire France Italy Russian Empire Kingdom of Serbia United States Central Powers: Austria-Hungary Bulgaria German Empire Ottoman Empire Commanders Douglas Haig John Jellicoe Ferdinand Foch Nikolay II Nikolay Yudenich Radomir Putnik Woodrow Wilson John Pershing Wilhelm II Reinhard Scheer Franz Josef I Oskar Potiorek Ä°smail... Flag Seal Nickname: Big Apple Location Location in the state of New York Government Counties (Boroughs) Bronx (The Bronx) New York (Manhattan) Queens (Queens) Kings (Brooklyn) Richmond (Staten Island) Mayor Michael Bloomberg (R) Geographical characteristics Area     City 1,214. ... The Washington Naval Conference was a diplomatic conference held in Washington, D.C. in 1921 and 1922. ...

In 1929, the State Department withdrew its share of the funding, the Army declined to bear the entire load, and the Black Chamber closed down MI-8. In his much later memoirs, then new Secretary of State Henry Stimson said that: "Gentlemen do not read each other's mail." His views on the worth of cryptanalysis had changed by the time he became Secretary of War during WWII, before and during which he, and the entire US command structure, relied heavily on decrypted enemy communications. 1929 (MCMXXIX) was a common year starting on Tuesday (link will take you to calendar). ... The United States Department of State, often referred to as the State Department, is the Cabinet-level foreign affairs agency of the United States government, equivalent to foreign ministries in other countries. ... In several countries, Secretary of State is a senior government position. ... Henry L. Stimson Henry Lewis Stimson (September 21, 1867 - October 20, 1950) was an American politician. ...

In 1931, and in need of money, Yardley wrote a book about MI-8, entitled The American Black Chamber. 1931 (MCMXXXI) was a common year starting on Thursday (link is to a full 1931 calendar). ...

The term "Black Chamber" predates Yardley's use of it in the title of his book. The first in a long line of cabinet noirs was established by King Henry IV of France in 1590 as part of the Poste aux Lettres. Its mission was to open, read and reseal letters, and great expertise was developed in the restoration of broken seals. In the knowledge that mail was being opened, correspondents began to develop systems to encrypt and decrypt their letters, the breaking of these codes giving birth to modern systematic scientific code breaking. The Black Chambers survived through to the Twentieth Century in a variety of guises and inspired similar organisations in other countries, such as the "Secret Office" of the British Office, and it is within this historical framework that Yardley uses the term. A Black chamber or black room is a secret room in a post office or telecommunications center used by state officials to conduct clandestine interception and surveillance of communications. ...

It was also used at about that time in Poland (see article on Marian Rejewski). Marian Rejewski (probably 1932, the year he first solved the Enigma machine). ...

External links

• NSA's pages on Herbert O. Yardley and the Black Chamber