Black Chamber

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.

Headed by Herbert O. Yardley (1889 - 1958), it was founded immediately following World War 1. Funded by the Army and the State Department, MI-8, was disguised as a New York City company that made commercial codes for businesses. However, their actual mission was to break the diplomatic codes of different nations.

In 1929, the State Department closed down MI-8. According to legend, Secretary of State Henry Stimson at that time spoke the famous sentence: “Gentlemen do not read each other’s mail.”

In 1931, and in need of money, Yardley wrote the book about MI-8 entitled 'The American Black Chamber', hence the name.