Elizebeth Smith Friedman (August 26, 1892 – October 31, 1980) was a cryptanalyst and author, and a pioneer in U.S. cryptography. The special spelling of her name (more commonly spelled "Elizabeth") is attributed to her mother, who disliked the prospect of Elizebeth ever being called "Eliza." She has been dubbed "America's first female cryptanalyst".

She was the wife of William F. Friedman, a notable cryptographer credited with numerous contributions to cryptology, but she enjoyed many successes in her own right, and it was Elizebeth who first introduced her husband to the field.

In 1962 described single-substitution alphabet decipherings of the Voynich Manuscript as "doomed to utter frustration".(Wikipedia page on the VM [1] refers]] Longtime Shakespeare enthusiasts, Mrs. Friedman and her husband, after retirement from government service, collaborated on a manuscript entitled "The Cryptologist Looks At Shakespeare", eventually published as The Shakespearian ciphers examined (Cambridge University Press, 1957). It won awards from the Folger Shakespeare Library and the American Shakespeare Theater and Academy. In this book, the Friedmans dismissed Baconians such as Mrs. Elizabeth Wells Gallup and Ignatius Donnelly with such technical proficiency and finesse that the book won far more acclaim than others addressing the same topic.

The work that Gallup had done earlier for Col Fabyan at Riverbank operated on two assumptions. One was that Bacon invented a biliteral cipher and that the cipher used in the original printed Shakespeare folios employed "an odd variety of typefaces." The Friedmans, however, "in a classic demonstration of their life's work," buried a hidden Baconian cipher on a page in their publication. It was an italicized phrase which, using the different type faces, expressed their final assessment of the controversy: "I did not write the plays. F. Bacon." Their book is regarded as the definitive work, if probably not the final word, on the subject.

Following her husband's death in 1969, Mrs. Friedman devoted much of retirement life to compiling a library and bibliography of his work. This "most extensive private collection of cryptographic material in the world" would finally be lodged in the George C. Marshall Research Library in Lexington, Virginia.

There is a fuller biography on Wikipedia at [2]; also here [3] and here National Security Agency, and many other articles.

The Friedmans donated their archives to the George C. Marshall Foundation.

See also Shakespearean authorship