Herbert Yardley

Herbert Yardley was a renowned American cryptographer and codebreaker who made significant contributions to the field of cryptography. Yardley's work had a profound impact on the development of cryptanalysis and intelligence gathering during World War I and the Interwar period. He is often credited with establishing the first cryptanalytic organization in the United States, which later became the National Security Agency (NSA). Yardley's expertise was sought after by prominent figures, including William Friedman and Frank Rowlett, who went on to become leading figures in the field of cryptology.

● Early Life and Education

Herbert Yardley was born in Worthington, Indiana, to a family of modest means. He developed an interest in codes and cryptography at an early age, inspired by the works of Edgar Allan Poe and Arthur Conan Doyle. Yardley attended the University of Chicago, where he studied philosophy and economics, and later worked as a telegraph operator for the U.S. State Department. During this time, he became acquainted with MI8, the U.S. Army's cryptanalytic unit, and began to develop his skills in codebreaking. Yardley's early work was influenced by the Zimmermann Telegram, which was intercepted and decoded by British intelligence during World War I.

● Career

Yardley's career in cryptanalysis began in earnest during World War I, when he was recruited by MI8 to work on breaking German and Austro-Hungarian codes. He worked closely with other notable cryptanalysts, including William Friedman and Charles J. Mendelsohn, to develop new techniques for codebreaking. Yardley's expertise was soon recognized, and he was appointed as the head of MI8's cryptanalytic unit. He played a key role in deciphering German and Austro-Hungarian communications, which contributed significantly to the Allied war effort. Yardley's work was also influenced by the Bolshevik Revolution and the subsequent establishment of the Cheka, the Soviet Union's intelligence agency.

● Black Chamber

In 1919, Yardley was appointed as the head of the Black Chamber, a cryptanalytic organization established by the U.S. State Department to intercept and decode foreign communications. The Black Chamber was a precursor to the National Security Agency (NSA) and was responsible for breaking codes and ciphers used by foreign governments, including those of Japan, Germany, and the Soviet Union. Yardley worked closely with other cryptanalysts, including Frank Rowlett and Abraham Sinkov, to develop new techniques for codebreaking. The Black Chamber was disbanded in 1929, due to concerns about its constitutionality and the ethics of intercepting foreign communications. Yardley's work during this period was influenced by the Washington Naval Conference and the subsequent establishment of the Japanese intelligence agency, the Kempeitai.

● Later Life and Legacy

After the disbandment of the Black Chamber, Yardley went on to write several books on cryptography and codebreaking, including The American Black Chamber and The Chinese Black Chamber. He also worked as a consultant for the Canadian and British governments, helping to establish their own cryptanalytic units. Yardley's legacy as a cryptanalyst and codebreaker is still recognized today, and his work continues to influence the field of cryptology. He is often credited with establishing the National Security Agency (NSA) and inspiring a new generation of cryptanalysts, including William Friedman and Frank Rowlett. Yardley's work was also influenced by the Enigma machine and the subsequent establishment of the British codebreaking unit at Bletchley Park.

● Writings and Publications

Yardley's writings on cryptography and codebreaking are still widely read and studied today. His book, The American Black Chamber, is considered a classic in the field and provides a detailed account of his work in cryptanalysis. Yardley also wrote The Chinese Black Chamber, which explores the history of Chinese cryptography and codebreaking. His other notable works include Japanese Diplomatic Codes and The Education of a Poker Player. Yardley's writings have been influential in shaping the field of cryptology and continue to be studied by cryptanalysts and historians around the world, including those at the National Security Agency (NSA), the Government Communications Headquarters (GCHQ), and the Australian Signals Directorate (ASD).