Click for homepage
William Friedman
The Dean of American Cryptology

William Frederick Friedman (24 September 1891 - 12 November 1969) was a United Status Army cryptographer, codebreaker, cipher machine developer and case officer. In the 1930s he worked for the Army's Signals Intelligence Service (SIS), and in 1949 he became head of the cryptographic division of the newly established Armed Forces Security Agency (AFSA). In 1952, when AFSA was succeeded by the National Security Agency (NSA), he became chief cryptologist of the NSA.

William 1 Friedman was born in 1892 in Kishinev (Moldovia), then part of the Russian Empire. His father, Frederic Friedman, was the son of a Romanian Jew from Bucharest, who worked at the Tsarist post office as a translator. His mother was the daughter of a successful wine merchant.

Barely a year after William was born, the family fled the country to escape the pogroms [2]. They emigrated to the United States and ended up in Pittsburgh, where William's father became a door-to-door salesman of Singer sewing machines. But with the fluctuating economy of western Pennsylvania, the Friedmans struggled to stay afloat and were always short on cash.

William turned out to be a gifted student and in 1909, following high school, he entered Cornell University as a genetics major. Six years later, in 1915, he was still in graduate school when the department chairman received a request from George Fabyan, a rich cotton merchant from Chicago. Fabiyan had established a research institute by the name of Riverbanks, in Geneva (Illinois, US) and was looking for bright students.

Genetics was one of the fields that were researched at Riverbanks Laboratories and Friedman became head of the Department of Genetics. Another subject that had the interest of the lab, was
code and ciphers. For its communication, Fabyan's firm – Bliss Fabyan and Company – used the cotton code, which was one of many commercial codes that were used at the time. This interest led him into the study of the Baconian theory of Shakespearean writing, for which he attracted a renowned expert: Elizabeth Wells Gallup. Like Friedman, she also ended up on Fabyan's payroll.

  1. William Friedman was initially born Wolf Friedman, but three years after emigrating to the United States, his first name was changed to William [1].

William (Bill) Friedman
William and Elizebeth Friedman in their house in Washington in July 1956
Same shot, but used as a postcard that was sent to Boris and Annie Hagelin on 17 July 1956
1 / 3
William (Bill) Friedman
2 / 3
William and Elizebeth Friedman in their house in Washington in July 1956
3 / 3
Same shot, but used as a postcard that was sent to Boris and Annie Hagelin on 17 July 1956

Friedman – who had meanwhile a established a reputation as an expert photographer – frequently joined Gallup on foreign trips to make photographs that she needed for her research. And it is in this capacity, that he fell in love with Gallop's assistent: Elizebeth Smith. He courted her, developed an interest in code and ciphers, and the two got married. Friedman became head of the Department of Code and Ciphers, and eventually abandonned genetics. The rest is history.

Soon after the outbreak of World War I (WWI), Fabyan acquired some War Department contracts to assist in breaking enemy codes. Friedman was persuaded to take service and soon became a renowned expert in the field. He was given a commission in the Army and was sent to France to assist in this new type of intelligence. At the end of the war he was a dedicated cryptologist. After the war he returned to Riverbanks but didn't stay long. He eventually left to join the Army again.

In 1921 he signed up with the Army as a civilian, where he became responsible for making secure codes. Elizebeth joined him and found employment in the same type of work. One of Friedman's duties was to evaluate foreign cryptographic machines for possible use by the Army. In 1927, he became acquainted with the Swedish company Aktiebolaget (AB) Cryptoteknik (later: Crypto AG).

As an executive secretary and technical advisor to the U.S. delegation to the International Telegraph Conference in Brussels, he was ordered to go to Sweden and meet developer Boris Hagelin, and learn more about the company and its products. Although the two didn't meet on that occasion, Friedman visited the factory and learned a great deal about the Hagelin machines.

World War II
Friedman write about the device:

It was about this time [1941] that a small mechanical machine, which had been developed and produced in quantity by a Swedish engineer in Stockholm named Hagelin, was brought to the attention of the Chief Signal Office (CSO) of the U.S. Army. [...] I turned in an unfavorable report on the machine for the reason that although its cryptosecurity was theoretically good, it had a low degree of cryptosecurity if improperly used. [...]
Nevertheless, Hagelin managed to close a deal with the US Army, in which his most recent creation — the C-38 — would be produced in large quantities in the US as the M-209, in return for the patent rights. The machine was used by the US Armed Forces for tactical traffic through­out the war, and made Hagelin a wealthy man.

The Gentleman's Agreement
After the war, Friedman stayed in contact with Boris Hagelin who, in 1952, moved his company from Sweden to neutral Switzerland, to evade the high tax burden and the restrictive export rules in Sweden. At the inititive of the AFSA (later: NSA), Friedman was appointed case officer to Hagelin, in order to persuade Hagelin not to sell secure equipment to certain countries [4].

In practice, it appeared to be very difficult to finalise the terms of an agreement between the NSA and Hagelin, mainly because of the bureaucratic attitude of the American agencies. Hagelin was never­theless willing to comply with the NSA's requests and shared the details of all his customers with them. He also promised not to supply his most secure machines to certain countries [4].

This secret deal – which was never put in writing – is known as The Gentleman's Agreement, and Friedman played a pivoting role in getting it in place. Over the years, the details of the agreement were revised several times, and even after Friedman's retirement in 1955, he would be recalled to intervene whenever there was a crisis (e.g. in 1957). Eventually, Hagelin would sell his company to a joint venture of the BND and the CIA in 1970, but by that time Friedman had already died [5].

 The Gentleman's Agreement

After Friedman's retirement – first in 1955 and again in 1957 – he stayed in contact with Boris Hagelin, who kept him informed about the developments in his company. Boris's son Bo, also stayed in contact with Friedman, although father and son were no longer on speaking terms.

But Friedman felt shut out, as the NSA no longer replied to his long letters and requests for information. Finally, in December of 1958, the NSA had had enough of his attempts to pry information out of people. On 30 December 1958, three NSA people turned up at his house and demanded access to his study, where they confiscated 48 items from his personal collection.

Friedman was furious. Apart from confiscating items from his personal correspondence, they had re-graded some of his (old) publications to the level of CONFIDENTIAL. This included his well-known (unclassified) book of 1923: The Index of Coincidence, and even an article about the writer Edgar Allan Poe that he had written for a literary journal in 1936. He would later take revenge.

In the late 1960s, Friedman's health began fail. He had promised Boris Hagelin to help him with the writing of his (Hagelin's) biography, but in April 1969, he returned the manuscript to Hagelin with the message that he had no energy left to finish it. He was hopeing that Hagelin would find a good biographer to complete the work. On 2 November 1969, Friedman died at the age of 78.

The Marshall Library Foundation
After his death, Friedman and his wife Elizebeth, donated their library (with all correspondence) to the George C. Marshall Foundation, rather than to the NSA. The reasons for this were simple. The hardliners within NSA wanted to remove cryptology completely from public view and would try to keep sensitive things under wraps forever, whilst for Friedman, sensitivity had an expiry date. In addition, this was Friedman's revenge for the fact that NSA had raided his study back in 1958.

In the years prior to his death, he and Elizebeth had worked tirelessly to prepare the library for donation. It was agreed that the Marshall Library would assign a separate room to the Friedman Collection, and that any sensitive material would be kept in a separate vault for the time being.

In December 1970, it arrived in 72 boxes at the Marshall Library. Additional material followed later in a closed safe of which only Elizebeth knew the combination. But even before the boxes had been fully unpacked, two NSA people turned up, to see if there was any information amoung the papers that could link Hagelin to American intelligence. They were particularly looking for personal correspondence between Friedman and Hagelin, but none was found.

The two NSA people returned in 1974 and again in 1975, but no under-classified material was ever found. To make matters worse, former NSA SIGINT officer Wayne Barker published a book in 1975 with the title: Cryptanalysis of the Hagelin Cryptograph, which revealed to the public that NSA had the ability to break Hagelin machines [6]. And having served in WWII, Barker was a credible source that could not be downplayed.
Affectionate postcard sent by Friedman to Boris Hagelin on 17 July 1956, showing Elizebeth and William Friedman in their study

On top of that, British writer Ronald Clark published his biography of William Friedman in 1977: The Man who Broke Purple, in which he gave an account of the friendship between Friedman and Hagelin [7]. Elizebeth Friedman had given Clark access to the private correspondence in the safe at the Friedman Room of the Marshall Library. But Clark failed to recognise the importance of Friedman's visits to Hagelin in Zug, and the consequences of the Gentleman's Agreement.

But just as they thought it couldn't get any worse, in late 1982, James Bamford published his book about the NSA: The Puzzle Palace [8], in which he gives a far more detailed account of the relationship between Friedman and Hagelin. Bamford's conclusion was that the visits to Zug, were probably to give NSA the ability to read NATO traffic. Unfortunately, he failed to recognise the importance of the 1953 meeting, in which the first Gentlemen's Agreement was discussed.

In 1981, NSA re-graded much of Friedman's documents to CONFIDENTIAL, 1 as a result of which they were no longer available to the public. The American Library Association (ALA) took the case to court, but lost. That didn't matter though; the existence of the Friedman-Hagelin file was now known to the public. In 2014, much of the material — by then known as the Friedman Collection — was partly declassified and released, albeit in a heavily redacted form. Since then, numerous articles based on the files have been published, including our The Gentleman's Agreement.

An that wasn't the end of it. In February 2020, after an investigation of more than two years, German TV station ZDF revealed the existence of Operation RUBICON — the secret purchase of Boris Hagelin's company – Crypto AG – by the German BND and the American CIA. Not only did it fill in the gaps of the redacted files, it also revealed what had happened after Friedman's death.

 Operation RUBICON

  1. This happened before James Bamford's book The Puzzle palace was published in 1982. NSA had acquired access to the galley proofs of his book prior to its going to print, so they knew what was coming.

  1. The Index of Coincidence and its Application in Cryptanalysis
    William F. Friedman. Abridged version if the 1922 release. 1

  2. The Index of Coincidence
    National Security Agency, January 1955. 1

  3. The Index of Coindidence and its Application in Cryptanalysis
    Aegean Park Press, 1987. ISBN 089412-137-5 (soft), 0-89412-138-3 (hard).

  4. Report on E Operations of the GC&CS at Bletchley Park
    Signal Security Agency, Washington. 12 August 1943. 2
  1. Declassified and approved for release by NSA on 6 January 2014 (E.O. 13526).
  2. Declassified by NARA on 6 June 2003.

  1. Ronald W. Clark, The Man Wo Broke Purple
    Biography of William (Bill) Friedman.
    ISBN 0-297-77279-1. 1977.
  1. Chris Christensen, Cryptanalysis of the Vigenère Cipher: The Friedman Test
    Spring 2015
  1. Wikipedia, William F. Friedman
    Retrieved July 2015.

  2. Wikipedia, Pogroms in the Russian Empire
    Retrieved December 2019.

  3. Wikipedia, Kishinev pogrom
    Retrieved December 2019.

  4. Paul Reuvers & Marc Simons, The Gentleman's Agreement
    Crypto Museum, 30 July 2015.

  5. Paul Reuvers & Marc Simons, Operation RUBICON
    Crypto Museum, 19 March 2020.

  6. Wayne Barker, Cryptanalysis of the Hagelin Cryptograph
    ISBN 0-89412-022-0. 1975.

  7. Ronald W. Clark, The Man Wo Broke Purple
    ISBN 0-297-77279-1. 1977.

  8. James Bamford, The Puzzle Palace
    ISBN 0-14-006748-5. 1982.
     James Bamford

  9. Wikipedia, Index of coincidence
    Retrieved January 2020.

  10. Jeffrey, Friedman Collection At Folger Library
    31 October 2014.

  11. NSA, William F. Friedman Collection of Official Papers
    Retrieved July 2015. 1
  1. Declassified by NSA on 17 June 2014 (EO 13526).

Further information
Any links shown in red are currently unavailable. If you like the information on this website, why not make a donation?
Crypto Museum. Last changed: Sunday, 03 September 2023 - 09:24 CET.
Click for homepage