William Frederick Friedman (September 24, 1891 – November 12, 1969) was a

US Army The United States Army (USA) is the land service branch of the United States Armed Forces. It is one of the eight U.S. uniformed services, and is designated as the Army of the United States in the U.S. Constitution.Article II, section 2, cla ...

cryptographer Cryptography, or cryptology (from grc, , translit=kryptós "hidden, secret"; and ''graphein'', "to write", or ''-logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of adver ...

who ran the research division of the Army's

Signal Intelligence Service The Signal Intelligence Service (SIS) was the United States Army codebreaking division through World War II. It was founded in 1930 to compile codes for the Army. It was renamed the Signal Security Agency in 1943, and in September 1945, became t ...

(SIS) in the 1930s, and parts of its follow-on services into the 1950s. In 1940, subordinates of his led by

Frank Rowlett Frank Byron Rowlett (May 2, 1908 – June 29, 1998) was an American cryptologist. Life and career Rowlett was born in Rose Hill, Lee County, Virginia and attended Emory & Henry College in Emory, Virginia. In 1929 he received a bachelor's d ...

broke Japan's PURPLE cipher, thus disclosing Japanese diplomatic secrets before America's entrance into

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...

Early life

Friedman was born Wolf Friedman ( yi, װאָלףֿ פֿרידמאַן, russian: Вольф Ф. Фридман), in Chişinău, Bessarabia, the son of Frederick Friedman, a Jew from

Bucharest Bucharest ( , ; ro, București ) is the capital and largest city of Romania, as well as its cultural, industrial, and financial centre. It is located in the southeast of the country, on the banks of the Dâmbovița River, less than north of ...

who worked as a

translator Translation is the communication of the meaning of a source-language text by means of an equivalent target-language text. The English language draws a terminological distinction (which does not exist in every language) between ''transl ...

and

linguist Linguistics is the scientific study of human language. It is called a scientific study because it entails a comprehensive, systematic, objective, and precise analysis of all aspects of language, particularly its nature and structure. Linguis ...

for the Russian Postal Service, and the daughter of a well-to-do wine merchant. Friedman's family fled Russia in 1892 to escape the virulent

anti-Semitism Antisemitism (also spelled anti-semitism or anti-Semitism) is hostility to, prejudice towards, or discrimination against Jews. A person who holds such positions is called an antisemite. Antisemitism is considered to be a form of racism. Antis ...

there, ending up in

Pittsburgh, Pennsylvania Pittsburgh ( ) is a city in the Commonwealth of Pennsylvania, United States, and the county seat of Allegheny County. It is the most populous city in both Allegheny County and Western Pennsylvania, the second-most populous city in Pennsylva ...

. Three years later, his first name was changed to William. As a child, Friedman was introduced to cryptography in the short story "

The Gold-Bug "The Gold-Bug" is a short story by American writer Edgar Allan Poe published in 1843. The plot follows William Legrand, who was bitten by a gold-colored bug. His servant Jupiter fears that Legrand is going insane and goes to Legrand's friend, an ...

" by

Edgar Allan Poe Edgar Allan Poe (; Edgar Poe; January 19, 1809 – October 7, 1849) was an American writer, poet, editor, and literary critic. Poe is best known for his poetry and short stories, particularly his tales of mystery and the macabre. He is wid ...

. He studied at the Michigan Agricultural College (known today as Michigan State University) in

East Lansing East Lansing is a city in the U.S. state of Michigan. Most of the city lies within Ingham County with a smaller portion extending north into Clinton County. At the 2020 Census the population was 47,741. Located directly east of the state capital ...

and received a scholarship to work on

genetics Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinian friar wor ...

Cornell University Cornell University is a private statutory land-grant research university based in Ithaca, New York. It is a member of the Ivy League. Founded in 1865 by Ezra Cornell and Andrew Dickson White, Cornell was founded with the intention to tea ...

. Meanwhile,

George Fabyan "Colonel" George Fabyan (1867 – 1936) was a millionaire businessman who founded a private research laboratory.Riverbank Laboratories outside

Chicago (''City in a Garden''); I Will , image_map = , map_caption = Interactive Map of Chicago , coordinates = , coordinates_footnotes = , subdivision_type = Country , subdivision_name ...

in September 1915. As head of the Department of Genetics, one of the projects he ran studied the effects of moonlight on crop growth, and so he experimented with the planting of

wheat Wheat is a grass widely cultivated for its seed, a cereal grain that is a worldwide staple food. The many species of wheat together make up the genus ''Triticum'' ; the most widely grown is common wheat (''T. aestivum''). The archaeologi ...

during various phases of the

moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...

Initial work in cryptology

Another of Fabyan's pet projects was research into secret messages which Sir

Francis Bacon Francis Bacon, 1st Viscount St Alban (; 22 January 1561 – 9 April 1626), also known as Lord Verulam, was an English philosopher and statesman who served as Attorney General and Lord Chancellor of England. Bacon led the advancement of both ...

had allegedly hidden in various texts during the reigns of

Elizabeth I Elizabeth I (7 September 153324 March 1603) was List of English monarchs, Queen of England and List of Irish monarchs, Ireland from 17 November 1558 until her death in 1603. Elizabeth was the last of the five House of Tudor monarchs and is ...

and

James I James I may refer to: People *James I of Aragon (1208–1276) *James I of Sicily or James II of Aragon (1267–1327) *James I, Count of La Marche (1319–1362), Count of Ponthieu *James I, Count of Urgell (1321–1347) *James I of Cyprus (1334–13 ...

. The research was carried out by Elizabeth Wells Gallup. She believed that she had discovered many such messages in the works of

William Shakespeare William Shakespeare ( 26 April 1564 – 23 April 1616) was an English playwright, poet and actor. He is widely regarded as the greatest writer in the English language and the world's pre-eminent dramatist. He is often called England's nation ...

, and convinced herself that Bacon had written many, if not all, of

Shakespeare William Shakespeare ( 26 April 1564 – 23 April 1616) was an English playwright, poet and actor. He is widely regarded as the greatest writer in the English language and the world's pre-eminent dramatist. He is often called England's natio ...

's works. Friedman had become something of an expert photographer while working on his other projects, and was asked to travel to England on several occasions to help Gallup photograph historical manuscripts during her research. He became fascinated with the work as he courted Elizebeth Smith, Gallup's assistant and an accomplished cryptographer. They married, and he soon became director of Riverbank's Department of Codes and Ciphers as well as its Department of Genetics. During this time, Friedman wrote a series of 8 papers on cryptography, collectively known as the " Riverbank Publications", including the first description of the index of coincidence, an important mathematical tool in cryptanalysis. With the entry of the United States into

World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...

, Fabyan offered the services of his Department of Codes and Ciphers to the government. No Federal department existed for this kind of work (although both the Army and Navy had had embryonic departments at various times), and soon Riverbank became the unofficial cryptographic center for the US Government. During this period, the Friedmans broke a code used by German-funded

India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...

n radicals in the US who planned to ship arms to

to gain independence from Britain. Analyzing the format of the messages, Riverbank realized that the code was based on a dictionary of some sort, a cryptographic technique common at the time. The Friedmans soon managed to decrypt most of the messages, but only long after the case had come to trial did the book itself come to light: a German-English dictionary published in 1880.

Signals Intelligence Service

The United States government decided to set up its own cryptological service, and sent Army officers to Riverbank to train under Friedman. To support the program, Friedman wrote a series of technical monographs, completing seven by early 1918. He then enlisted in the Army and went to France to serve as the personal cryptographer for General John J. Pershing. He returned to the US in 1920 and published an eighth monograph, "The Index of Coincidence and its Applications in Cryptography", considered by some to be the most important publication in modern cryptography to that time. His texts for Army cryptographic training were well thought of and remained classified for several decades. In 1921 he became chief cryptanalyst for the War Department and later led the Signals Intelligence Service (SIS)—a position he kept for a quarter century. In 1929, after The American

Black Chamber The Black Chamber (1919–1929), also known as the Cipher Bureau, was the United States' first peacetime cryptanalytic organization, and a forerunner of the National Security Agency. The only prior codes and cypher organizations maintained by th ...

in New York City was disbanded, its files were entrusted to SIS, and the cryptographic and intelligence services was reorganized to suit its new position at the War Department. Friedman coined several terms, including " cryptanalysis", and wrote many monographs on cryptography. One of these (written mostly in his spare time) was the first draft of his ''Elements of cryptanalysis'', which later was expanded to four volumes and became the U.S. Army's cryptographic main textbook and reference. Realizing that mathematical and language skills were essential to SIS' work, Friedman managed to get authority to hire three men with both mathematical training and language knowledge. They were

Solomon Kullback Solomon Kullback (April 3, 1907August 5, 1994) was an American cryptanalyst and mathematician, who was one of the first three employees hired by William F. Friedman at the US Army's Signal Intelligence Service (SIS) in the 1930s, along with Fra ...

and

Abraham Sinkov Abraham Sinkov (August 22, 1907 – January 19, 1998) was a US cryptanalyst. An early employee of the U.S. Army's Signals Intelligence Service, he held several leadership positions during World War II, transitioning to the new National Security A ...

, each of whom went on to distinguished service for decades. In addition he also was finally able to hire a man fluent in Japanese, John Hurt. During this period

Elizebeth Friedman Elizebeth Smith Friedman (August 26, 1892 – October 31, 1980) was an American cryptanalyst and author who deciphered enemy codes in both World Wars and helped to solve international smuggling cases during Prohibition. Over the course of her ...

continued her own work in cryptology, and became famous in a number of trials involving rum-runners and the

Coast Guard A coast guard or coastguard is a maritime security organization of a particular country. The term embraces wide range of responsibilities in different countries, from being a heavily armed military force with customs and security duties to ...

and

FBI The Federal Bureau of Investigation (FBI) is the domestic intelligence and security service of the United States and its principal federal law enforcement agency. Operating under the jurisdiction of the United States Department of Justice, t ...

during

Prohibition Prohibition is the act or practice of forbidding something by law; more particularly the term refers to the banning of the manufacture, storage (whether in barrels or in bottles), transportation, sale, possession, and consumption of alcohol ...

Solution of cipher machines

During the 1920s, several new cipher machines were developed generally based on using

typewriter A typewriter is a mechanical or electromechanical machine for typing characters. Typically, a typewriter has an array of keys, and each one causes a different single character to be produced on paper by striking an inked ribbon selectivel ...

mechanics and basic electrical circuitry. An early example was the Hebern Rotor Machine, designed in the US in 1915 by

Edward Hebern Edward Hugh Hebern (April 23, 1869 – February 10, 1952) was an early inventor of rotor machines, devices for encryption. Background Edward Hugh Hebern was born in Streator, Illinois on April 23, 1869. His parents were Charles and Rosanna (Ro ...

. This system offered such security and simplicity of use that Hebern heavily promoted it to investors. Friedman realized that the new rotor machines would be important, and devoted some time to analyzing Hebern's design. Over a period of years, he developed principles of analysis and discovered several problems common to most rotor-machine designs. Examples of some dangerous features which allowed cracking of the generated code included having rotors step one position with each keypress, and putting the fastest rotor (the one that turns with every keypress) at either end of the rotor series. In this case, by collecting enough

ciphertext In cryptography, ciphertext or cyphertext is the result of encryption performed on plaintext using an algorithm, called a cipher. Ciphertext is also known as encrypted or encoded information because it contains a form of the original plaintext ...

and applying a standard statistical method known as the kappa test, he showed that he could, albeit with great difficulty, crack any cipher generated by such a machine. SIGABA-ECM (Army M-134-C, Navy CSP-888) at NCM side view

SIGABA-ECM (Army M-134-C, Navy CSP-888) at NCM side view

Friedman used his understanding of rotor machines to develop several that were immune to his own attacks. The best of the lot was the SIGABA—which was destined to become the US's highest-security cipher machine in

after improvements by

and

Laurance Safford Captain, U.S.N. Laurance Frye Safford (October 22, 1893 – May 15, 1973) was a U.S. Navy cryptologist. He established the Naval cryptologic organization after World War I, and headed the effort more or less constantly until shortly after the ...

. Just over 10,000 were built. A patent on SIGABA was filed at the end of 1944, but kept secret until 2001, long after Friedman had died, when it was finally issued as . In 1939, the Japanese introduced a new cipher machine for their most sensitive diplomatic traffic, replacing an earlier system that SIS referred to as "RED." The new cipher, which SIS called "

PURPLE Purple is any of a variety of colors with hue between red and blue. In the RGB color model used in computer and television screens, purples are produced by mixing red and blue light. In the RYB color model historically used by painters, ...

", was different and much more difficult. The Navy's cryptological unit (

OP-20-G OP-20-G or "Office of Chief Of Naval Operations (OPNAV), 20th Division of the Office of Naval Communications, G Section / Communications Security", was the U.S. Navy's signals intelligence and cryptanalysis group during World War II. Its mission ...

) and the SIS thought it might be related to earlier Japanese cipher machines, and agreed that SIS would handle the attack on the system. After several months trying to discover underlying patterns in PURPLE ciphertexts, an SIS team led by Friedman and Rowlett, in an extraordinary achievement, figured it out. PURPLE, unlike the German

Enigma Enigma may refer to: *Riddle, someone or something that is mysterious or puzzling Biology *ENIGMA, a class of gene in the LIM domain Computing and technology * Enigma (company), a New York-based data-technology startup * Enigma machine, a family ...

or the Hebern design, did not use

rotor Rotor may refer to: Science and technology Engineering * Rotor (electric), the non-stationary part of an alternator or electric motor, operating with a stationary element so called the stator *Helicopter rotor, the rotary wing(s) of a rotorcraft ...

s but stepper switches like those in automated telephone exchanges.

Leo Rosen Leo Rosen was a U.S. cryptanalyst who worked with Frank Rowlett at Signals Intelligence Service (S.I.S.) before the start of World War II on Japanese ciphers. Rowlett found a method to read the messages enciphered on the Japanese PURPLE machine ...

of SIS built a machine using — as was later discovered — the identical model of switch that the Japanese designer had chosen. Thus, by the end of 1940, SIS had constructed an exact analog of the PURPLE machine without ever having seen one. With the duplicate machines and an understanding of PURPLE, SIS could decrypt increasing amounts of Japanese traffic. One such intercept was the message to the Japanese Embassy in Washington, D.C., ordering an end (on December 7, 1941) to negotiations with the US. The message gave a clear indication of impending

war War is an intense armed conflict between states, governments, societies, or paramilitary groups such as mercenaries, insurgents, and militias. It is generally characterized by extreme violence, destruction, and mortality, using regular o ...

, and was to have been delivered to the US State Department only hours prior to the

attack on Pearl Harbor The attack on Pearl HarborAlso known as the Battle of Pearl Harbor was a surprise military strike by the Imperial Japanese Navy Air Service upon the United States against the naval base at Pearl Harbor in Honolulu, Territory of Hawaii ...

. The controversy over whether the US had foreknowledge of the Pearl Harbor attack has roiled well into the 21st century. In 1941, Friedman was hospitalized with a "

nervous breakdown A mental disorder, also referred to as a mental illness or psychiatric disorder, is a behavioral or mental pattern that causes significant distress or impairment of personal functioning. Such features may be persistent, relapsing and remitt ...

", widely attributed to the mental strain of his work on PURPLE. While he remained in hospital, a four-man team —

and

from SIS, and Lt. Prescott Currier and Lt. Robert Weeks from the U.S. Navy's OP-20-G — visited the British establishment at the "

Government Code and Cypher School Government Communications Headquarters, commonly known as GCHQ, is an intelligence and security organisation responsible for providing signals intelligence (SIGINT) and information assurance (IA) to the government and armed forces of the Uni ...

" at

Bletchley Park Bletchley Park is an English country house and estate in Bletchley, Milton Keynes ( Buckinghamshire) that became the principal centre of Allied code-breaking during the Second World War. The mansion was constructed during the years followin ...

. They gave the British a PURPLE machine, in exchange for details on the design of the Enigma machine and on how the British decrypted the Enigma cipher. However Friedman visited Bletchley Park in April 1943 and played a key role in drawing up the 1943 BRUSA Agreement.

National Security Agency

Following World War II, Friedman remained in government signals intelligence. In 1949 he became head of the cryptographic division of the newly formed Armed Forces Security Agency (AFSA) and in 1952 became chief cryptologist for the

National Security Agency The National Security Agency (NSA) is a national-level intelligence agency of the United States Department of Defense, under the authority of the Director of National Intelligence (DNI). The NSA is responsible for global monitoring, collect ...

(NSA) when it was formed to take over from AFSA. Friedman produced a classic series of textbooks, " Military Cryptanalysis", which was used to train NSA students. (These were revised and extended, under the title " Military Cryptanalytics", by Friedman's assistant and successor Lambros D. Callimahos, and used to train many additional cryptanalysts.) During his early years at NSA, he encouraged it to develop what were probably the first super-computers, although he was never convinced a machine could have the "insight" of a human mind. Friedman spent much of his free time trying to decipher the famous

Voynich Manuscript The Voynich manuscript is an illustrated codex hand-written in an otherwise unknown writing system, referred to as 'Voynichese'. The vellum on which it is written has been carbon-dated to the early 15th century (1404–1438), and stylistic ana ...

, said to be written sometime between 1403–1437. However, after four decades of study he finally had to admit defeat, contributing no more than an educated guess as to its origins and meaning. In 1955, Friedman initiated, on behalf of the NSA, a secret agreement with

Crypto AG Crypto AG was a Swiss company specialising in communications and information security founded by Boris Hagelin in 1952. The company was secretly purchased for US $5.75 million and jointly owned by the American Central Intelligence Agency (CIA) a ...

, a Swiss manufacturer of encryption machines. The agreement resulted in many of the company's machines being compromised, so that the messages produced by them became crackable by the NSA. Friedman retired in 1956 and, with his wife, turned his attention to the problem that had originally brought them together: examining Bacon's supposed codes. Together they wrote a book entitled ''The Cryptologist Looks at Shakespeare'', which won a prize from the

Folger Library The Folger Shakespeare Library is an independent research library on Capitol Hill in Washington, D.C., United States. It has the world's largest collection of the printed works of William Shakespeare, and is a primary repository for rare materia ...

and was published under the title ''The Shakespearean Ciphers Examined.'' The book demonstrated flaws in Gallup's work and in that of others who sought hidden ciphers in Shakespeare's work. At NSA's request Friedman prepared ''Six Lectures Concerning Cryptography and Cryptanalysis'', which he delivered at NSA. But later the Agency, concerned about security, confiscated the reference materials from Friedman's home.

Death and legacy

Friedman's health began to fail in the late 1960s, and he died in 1969. Friedman and his wife Elizebeth are buried in

Arlington National Cemetery Arlington National Cemetery is one of two national cemeteries run by the United States Army. Nearly 400,000 people are buried in its 639 acres (259 ha) in Arlington, Virginia. There are about 30 funerals conducted on weekdays and 7 held on Sa ...

. Friedman and his wife donated their archives to the library of the

George C. Marshall Foundation The George C. Marshall Foundation in Lexington, Virginia, was commissioned by President Harry S. Truman in order to preserve the papers of General George Marshall, George C. Marshall. Marshall served as Army chief of staff, secretary of state and d ...

, which also has had material reclassified and removed by the NSA. Friedman has been inducted into the

Military Intelligence Hall of Fame The Military Intelligence Hall of Fame is a hall of fame established by the Military Intelligence Corps of the United States Army in 1988 to honor soldiers and civilians who have made exceptional contributions to military intelligence. The hall is ...

and there is a building named after William and Elizebeth at the NSA complex at Fort George G. Meade in Maryland. He was also presented the

Medal for Merit The Medal for Merit was, during the period it was awarded, the highest civilian decoration of the United States. It was awarded by the President of the United States to civilians who "distinguished themselves by exceptionally meritorious conduct i ...

by President

Harry Truman Harry S. Truman (May 8, 1884December 26, 1972) was the 33rd president of the United States, serving from 1945 to 1953. A leader of the Democratic Party, he previously served as the 34th vice president from January to April 1945 under Franklin ...

, and the National Security Medal by Dwight Eisenhower. Friedman has the distinction of having one of the longest known suppressed patent applications, for , a patent for a "cryptographic system". It was filed on July 25, 1933, issued on August 1, 2000. Friedman Hall, located on Fort Huachuca,

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...

, is named in his honor.

Children

Friedman had two children with his wife, Elizebeth. Barbara Friedman (later Atchison) (born 1923), and John Ramsay Friedman (1926–2010).

In popular culture

Commander Schoen, a character appearing in Neal Stephenson's novel ''

Cryptonomicon ''Cryptonomicon'' is a 1999 novel by American author Neal Stephenson, set in two different time periods. One group of characters are World War II-era Allied codebreakers and tactical-deception operatives affiliated with the Government Code an ...

'', is to a large extent inspired by Friedman. Schoen shares a significant background and personality traits with Friedman, including being one of the top cryptanalysts of the U.S. Army, breaking Japanese codes prior to Japan's involvement in World War II, and the psychological problems that he suffered from as a result. In his acknowledgements, Stephenson writes "Among all these great wartime hackers, some kind of special recognition must go to William Friedman, who sacrificed his health to break the Japanese machine cipher called Purple before the war even began."

Awards and honors

* 1944: Commendation for Exceptional Civilian Service * 1946:

* 1955: National Security Medal.

Publications

* "The index of coincidence and its applications in cryptography" (1922). Department of Ciphers. Publ 22. Geneva, Illinois, USA: Riverbank Laboratories. . *
2nd ed.
(1935). Washington, D.C.: Signals Office,

War Department War Department may refer to: * War Department (United Kingdom) * United States Department of War (1789–1947) See also * War Office, a former department of the British Government * Ministry of defence * Ministry of War * Ministry of Defence * D ...

.
"Preliminary Historical Report on the Solution of the 'B' Machine"
(Oct. 14, 1960).

References

Bibliography

* Clark, Ronald W. (1977). ''The Man Who Broke Purple: the Life of Colonel William F. Friedman, Who Deciphered the Japanese Code in World War II''. Boston: Little Brown & Co. . . * Friedman, William F. (1984). Six Lectures on Cryptology. U.S. National Security Agency, 1965, declassified 1977. * Gannon, James (2001). ''Stealing Secrets, Telling Lies: How Spies and Codebreakers Helped Shape the Twentieth Century''. Washington, D.C.: Brassey's. . . * Kahn, David (1966). ''The Codebreakers: the Story of Secret Writing''. London: Weidenfeld and Nicolson. . * Rowlett, Frank B. (1999). ''The Story of Magic: Memoirs of an American Cryptologic Pioneer''. Laguna Hills, Calif.: Aegean Park Press. . . * Jensen, Cora J. (apparently William Friedman) (Oct. 28, 1920)
"'Saying It' in Cipher."
''The Florists’ Review'', vol. XLVI, no. 1196. p. 17. * ''Methods for the Reconstruction of Primary Alphabets'', with Elizebeth S. Friedman. Riverbank Publication, no. 21 (1918). In
''Methods for the Solution of Ciphers, Publications 15-22 ''.
Rufus A. Long Digital Library of Cryptography, George C. Marshall Library. * For references to other material, se
''The Friedman Collection: An Analytical Guide''.

External links

William F. Friedman Papers
at

Friedman Cryptologic Collection
at

NSA Hall of Honor page on Friedman

NSA William F. Friedman Collection of Official Papers

Colonel William F. Friedman (the Godfather of Cryptology)
by Robert A. Reeves

of Friedman's work were available through

Aegean Park Press Aegean Park Press was a publisher based in Walnut Creek, California, specializing in cryptology, military intelligence, contract bridge and Mayan languages. The company's books on cryptology were "mostly reprints of fairly advanced texts, " cluding ...

{{DEFAULTSORT:Friedman, William F. 1891 births 1969 deaths People from Kishinyovsky Uyezd Moldovan Jews Bessarabian Jews Emigrants from the Russian Empire to the United States American cryptographers American people of Moldovan-Jewish descent Riverbank Laboratories Baconian theory of Shakespeare authorship Mathematicians from Illinois People from Kane County, Illinois People from Washington, D.C. Cornell University alumni Michigan State University alumni American people of World War I American people of World War II Military personnel from Pittsburgh National Security Agency cryptographers Signals Intelligence Service cryptographers Medal for Merit recipients Burials at Arlington National Cemetery People from Chișinău