On This Day — Remembering Navy Cryptanalyst Agnes Meyer Driscoll (July 24, 1889 – September 16, 1971) [2020]

“Once the pursuit of truth begins to haunt the mind, it becomes an ideal never wholly attained.”

“We can never achieve absolute truth but we can live hopefully by a system of calculated probabilities.”

Agnes Meyer Driscoll

“In her thirty-year career, Mrs. Driscoll broke Japanese Navy manual codes — the Red Book Code in the 1920s, the Blue Book Code in 1930, and, in 1940, she made critical inroads into JN-25, the Japanese fleet’s operational code, which the U.S. Navy exploited after the attack on Pearl Harbor for the rest of the Pacific War.”

NSA — Hall of Honor

July 24 2019 — Agnes Meyer Driscoll (July 24, 1889 – September 16, 1971), known as Miss Aggie or Madame X, was an American cryptanalyst during both World War I and World War II. Follow us on Twitter: @Intel_Today

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UPDATE (July 24 2020) — Kevin Wade Johnson — Historian at The Center for Cryptologic History — has published her full biography: “The Neglected Giant: Agnes Meyer Driscoll“.

Although Agnes May Meyer, later Agnes May Driscoll,* was the Navy’s principal cryptanalyst of many years, spent over 40 years in cryptology, became a member of the Cryptologic Hall of Honor, and has principal credit for personally breaking two major codes/ ciphers, she was curiously neglected during her career and after.

Never credited with as much as she believed was her due, never promoted in grade with her peers, even now she is not always ranked with those she regarded as peers. Although considered one of the giants of American cryptology, she is nevertheless rarely mentioned in the same breath as a William Friedman or a Laurance Safford, even though she began her code and cipher work in 1918, contemporary with Friedman. Should she be ranked with them? Has she been neglected by history? We will consider exactly that.


Agnes Driscoll unquestionably had flaws and faults. But those do not diminish what a giant she was. She lifted Navy cryptology up as high as anyone and rose high in the esteem of those she worked most closely with.

She rose as high as her talents, organizational limitations, and her wishes suited her. She towers above nearly all her contemporaries. Let us not lose sight of her limitations but still admire her for all that she did and all that she was. Agnes Driscoll is one of the true giants of cryptology, and one we can all look up to. Let us neglect her no more.

I have long argued that the importance of her work had yet to be fully acknowledged. I believe that people are slowly beginning to realize the giant she was.


Agnes Driscoll joined the U.S. Navy in 1918, with a degree in mathematics and physics, and a proficiency in English, French, German, Latin, and Japanese.

Edwin T. Layton described Driscoll as “without peer as a cryptanalyst”.

“She worked in their cryptologic office throughout World War I.

Staying with the Navy as a civilian, Mrs. Driscoll was instrumental in breaking Japanese naval systems between the wars. In 1930, she solved the Japanese system used during their Grand Maneuvers.

The information learned indicated that the Japanese knew American operational plans.

Later, she broke the Japanese “Blue Book” which required solving both the code and the overlaying cipher simultaneously.

Mrs. Driscoll also assisted in the development of an early cipher machine and encouraged the use of tabulating machines for cryptanalysis. She retired from NSA in 1959.”

In ‘The Emperor’s Codes’ — a book about breaking Japan’s secret ciphers by Michael Smith — Agnes Driscoll is mentioned only twice (Pages 218 & 278).

This is perhaps a sign that the importance of her work has yet to be fully acknowledged.

The NSA Hall of Honor was created in 1999 to pay special tribute to the pioneers and heroes who rendered distinguished service to American cryptology.

In 2000 she was inducted into the National Security Agency’s Hall of Honor.

PS: Many experts believe that JN-25 — the Japanese fleet’s operational code — could have been broken before the attack on Pearl Harbor.

The Life of Agnes Meyer Driscoll


Agnes Meyer Driscoll — Wikipedia

Remembering Navy Cryptanalyst, Mrs. Agnes Meyer Driscoll — Station HYPO


Remembering Navy Cryptanalyst Agnes Meyer Driscoll (July 24, 1889 – September 16, 1971)

On This Day — Remembering Navy Cryptanalyst Agnes Meyer Driscoll (July 24, 1889 – September 16, 1971)

On This Day — Remembering Navy Cryptanalyst Agnes Meyer Driscoll (July 24, 1889 – September 16, 1971) [2019]

On This Day — Remembering Navy Cryptanalyst Agnes Meyer Driscoll (July 24, 1889 – September 16, 1971) [2020]

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