Hut 7
Encyclopedia
Hut 7 was a wartime section of the Government Code and Cypher School in Bletchley Park
tasked with the solution of Japanese naval codes such as JN4, JN11, JN40, and JN25. The hut was headed by Hugh Foss
who reported to Frank Birch
, the head of Bletchley's Naval section.
Hut 7 supplied cryptanalysts and linguists to Bletchley’s front line station the Far East Combined Bureau
(FECB) at Hong Kong, then Singapore, then Anderson Station (Colombo
, Ceylon, now Sri Lanka), and finally Allidina School in Kilindini, Kenya
.
Bletchley co-operated with the US Navy Code and Signals Section known as OP-20-G
in Washington D.C., and with FRUMEL
in Melbourne (although the reciprocal cooperation from Fabian at FRUMEL was limited and reluctant).
and romaji Morse code
system used by the Japanese. GCCS began breaking Japanese diplomatic traffic in the early 1920s. GCCS subsequently attacked the Naval Reporting Code, and General Operations Code.
The section was headed by William "Nobby" Clarke with Harry Shaw and Ernest Hobert-Hampden. These were later joined by Eric Nave
, seconded from the Royal Australian Navy
, John Tiltman, and Hugh Foss
.
GCCS operated the Far East Combined Bureau
, the codebreaking and intercept station in Hong Kong
prewar, which during the war moved to Singapore
, Colombo and Kilindini.
and the University of Oxford
by referral through people like the Revd Martin Charlesworth, A.D. Lindsay, Dr C. P. Snow
, and Theodore Chaundy. Candidates were interviewed and approved by a board that included Colonel Tiltman. Successful candidates received a final interview at Bletchley by a senior representative of their section.
At the outset of the war, Britain had few Japanese linguists and conventional wisdom held that it would require two years to produce qualified linguists for the war effort. In February 1942, an accelerated program was established to train linguists to assist with Japanese signals intelligence. Candidates were put through an intensive six month course taught by Captain Oswald Tuck, RN. The course was taught in various locations in Bedford including the Gas Company. The course produced linguists for the Navy, Army, Air Force, and Foreign Office. Some of the linguists were sent on to Bletchley, while others were sent to London to work with Captain Malcolm Kennedy.
Later cryptanalysts did not require linguistic training, so could be recruited and put to work directly. Some of these cryptanalysts received a shorter version of the Japanese language course.
The Japanese Naval Section was originally stationed at the Elmer School near Bletchley. By August 1942 the unit consisted of 40 people. The unit was moved inside Bletchley Park in September and again in February 1943 to Hut 7. The unit expanded (or moved) later to Block B.
also utilized electric cipher machines known as JADE
and CORAL
using the same technology as PURPLE
. While OP-20-G took the lead on these systems, Bletchley provided some contributions.
In 1921, GCCS was able to provide insight into the Japanese bargaining position at the Washington Naval Conference
of the nine major powers and limit their ambitions.
Pre-war accomplishments were helped tremendously by the death of Emperor Taishō
in 1926. The repetition of the formal announcement provided GCCS with cribs
into almost every code in use. Later in 1934, Foss was able to break an early Japanese cipher machine.
Tiltman provided the major break into JN25 in 1939.
In early 1942, decrypts from Anderson gave advance warning of Vice Admiral Nagumo
's Indian Ocean raid
including a planned attack on Colombo. The warning allowed the British to limit damage, improve opposition, and evacuate the fleet and the cryptanalysts from Colombo to Kilindini.
In May 1945, the team at HMS Anderson successfully broke a message in JN25 that provided details of a supply convoy going from Singapore to the Andaman Islands. This message provided details that led to the sinking of the Japanese cruiser Haguro
in the Battle of the Malacca Strait.
Bletchley Park
Bletchley Park is an estate located in the town of Bletchley, in Buckinghamshire, England, which currently houses the National Museum of Computing...
tasked with the solution of Japanese naval codes such as JN4, JN11, JN40, and JN25. The hut was headed by Hugh Foss
Hugh Foss
Hugh Rose Foss was a British cryptographer.-Life:Foss was born in Kobe, Japan, where his father the Rt Revd Hugh Foss was a missionary bishop, and he learned Japanese....
who reported to Frank Birch
Frank Birch
Frank Birch was an English actor.- Selected filmography :...
, the head of Bletchley's Naval section.
Hut 7 supplied cryptanalysts and linguists to Bletchley’s front line station the Far East Combined Bureau
Far East Combined Bureau
The Far East Combined Bureau, an outstation of the British Government Code and Cypher School, was set up in Hong Kong in March 1935, to monitor Japanese, and also Chinese and Russian intelligence and radio traffic...
(FECB) at Hong Kong, then Singapore, then Anderson Station (Colombo
Colombo
Colombo is the largest city of Sri Lanka. It is located on the west coast of the island and adjacent to Sri Jayawardenapura Kotte, the capital of Sri Lanka. Colombo is often referred to as the capital of the country, since Sri Jayawardenapura Kotte is a satellite city of Colombo...
, Ceylon, now Sri Lanka), and finally Allidina School in Kilindini, Kenya
Kenya
Kenya , officially known as the Republic of Kenya, is a country in East Africa that lies on the equator, with the Indian Ocean to its south-east...
.
Bletchley co-operated with the US Navy Code and Signals Section known as OP-20-G
OP-20-G
OP-20-G or "Office of Chief Of Naval Operations , 20th Division of the Office of Naval Communications, G Section / Communications Security", was the US Navy's signals intelligence and cryptanalysis group during World War II. Its mission was to intercept, decrypt, and analyze naval communications...
in Washington D.C., and with FRUMEL
FRUMEL
Fleet Radio Unit, Melbourne was a United States-Australian-British signals intelligence unit, based in Melbourne, Australia during World War II. It was one of two major Allied signals intelligence units, called Fleet Radio Units, in the Pacific theatres, the other being FRUPAC , in Hawaii...
in Melbourne (although the reciprocal cooperation from Fabian at FRUMEL was limited and reluctant).
Pre-War Origins
Among the first challenges was overcoming the special kanaKana
Kana are the syllabic Japanese scripts, as opposed to the logographic Chinese characters known in Japan as kanji and the Roman alphabet known as rōmaji...
and romaji Morse code
Morse code
Morse code is a method of transmitting textual information as a series of on-off tones, lights, or clicks that can be directly understood by a skilled listener or observer without special equipment...
system used by the Japanese. GCCS began breaking Japanese diplomatic traffic in the early 1920s. GCCS subsequently attacked the Naval Reporting Code, and General Operations Code.
The section was headed by William "Nobby" Clarke with Harry Shaw and Ernest Hobert-Hampden. These were later joined by Eric Nave
Eric Nave
Captain Eric Nave was a Navy Paymaster Commander and an Australian cryptographer, before and during World War II. He served in the Navy from 1917 to 1949. As a midshipman in the 1920s, he was required to learn a foreign language and chose Japanese: with French and German you got sixpence a day...
, seconded from the Royal Australian Navy
Royal Australian Navy
The Royal Australian Navy is the naval branch of the Australian Defence Force. Following the Federation of Australia in 1901, the ships and resources of the separate colonial navies were integrated into a national force: the Commonwealth Naval Forces...
, John Tiltman, and Hugh Foss
Hugh Foss
Hugh Rose Foss was a British cryptographer.-Life:Foss was born in Kobe, Japan, where his father the Rt Revd Hugh Foss was a missionary bishop, and he learned Japanese....
.
GCCS operated the Far East Combined Bureau
Far East Combined Bureau
The Far East Combined Bureau, an outstation of the British Government Code and Cypher School, was set up in Hong Kong in March 1935, to monitor Japanese, and also Chinese and Russian intelligence and radio traffic...
, the codebreaking and intercept station in Hong Kong
Hong Kong
Hong Kong is one of two Special Administrative Regions of the People's Republic of China , the other being Macau. A city-state situated on China's south coast and enclosed by the Pearl River Delta and South China Sea, it is renowned for its expansive skyline and deep natural harbour...
prewar, which during the war moved to Singapore
Singapore
Singapore , officially the Republic of Singapore, is a Southeast Asian city-state off the southern tip of the Malay Peninsula, north of the equator. An island country made up of 63 islands, it is separated from Malaysia by the Straits of Johor to its north and from Indonesia's Riau Islands by the...
, Colombo and Kilindini.
WWII Expansion
Potential linguists and cryptographers were recruited from the University of CambridgeUniversity of Cambridge
The University of Cambridge is a public research university located in Cambridge, United Kingdom. It is the second-oldest university in both the United Kingdom and the English-speaking world , and the seventh-oldest globally...
and the University of Oxford
University of Oxford
The University of Oxford is a university located in Oxford, United Kingdom. It is the second-oldest surviving university in the world and the oldest in the English-speaking world. Although its exact date of foundation is unclear, there is evidence of teaching as far back as 1096...
by referral through people like the Revd Martin Charlesworth, A.D. Lindsay, Dr C. P. Snow
C. P. Snow
Charles Percy Snow, Baron Snow of the City of Leicester CBE was an English physicist and novelist who also served in several important positions with the UK government...
, and Theodore Chaundy. Candidates were interviewed and approved by a board that included Colonel Tiltman. Successful candidates received a final interview at Bletchley by a senior representative of their section.
At the outset of the war, Britain had few Japanese linguists and conventional wisdom held that it would require two years to produce qualified linguists for the war effort. In February 1942, an accelerated program was established to train linguists to assist with Japanese signals intelligence. Candidates were put through an intensive six month course taught by Captain Oswald Tuck, RN. The course was taught in various locations in Bedford including the Gas Company. The course produced linguists for the Navy, Army, Air Force, and Foreign Office. Some of the linguists were sent on to Bletchley, while others were sent to London to work with Captain Malcolm Kennedy.
Later cryptanalysts did not require linguistic training, so could be recruited and put to work directly. Some of these cryptanalysts received a shorter version of the Japanese language course.
The Japanese Naval Section was originally stationed at the Elmer School near Bletchley. By August 1942 the unit consisted of 40 people. The unit was moved inside Bletchley Park in September and again in February 1943 to Hut 7. The unit expanded (or moved) later to Block B.
Contributions
In addition to code books and manual ciphers, the Imperial Japanese NavyImperial Japanese Navy
The Imperial Japanese Navy was the navy of the Empire of Japan from 1869 until 1947, when it was dissolved following Japan's constitutional renunciation of the use of force as a means of settling international disputes...
also utilized electric cipher machines known as JADE
JADE
JADE was the codename given by US codebreakers to a Japanese World War II cipher machine. The Imperial Japanese Navy used the machine for communications from late 1942 until 1944...
and CORAL
Coral
Corals are marine animals in class Anthozoa of phylum Cnidaria typically living in compact colonies of many identical individual "polyps". The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.A coral "head" is a colony of...
using the same technology as PURPLE
PURPLE
In the history of cryptography, 97-shiki ōbun inji-ki or Angōki Taipu-B , codenamed Purple by the United States, was a diplomatic cryptographic machine used by the Japanese Foreign Office just before and during World War II...
. While OP-20-G took the lead on these systems, Bletchley provided some contributions.
In 1921, GCCS was able to provide insight into the Japanese bargaining position at the Washington Naval Conference
Washington Naval Conference
The Washington Naval Conference also called the Washington Arms Conference, was a military conference called by President Warren G. Harding and held in Washington from 12 November 1921 to 6 February 1922. Conducted outside the auspices of the League of Nations, it was attended by nine nations...
of the nine major powers and limit their ambitions.
Pre-war accomplishments were helped tremendously by the death of Emperor Taishō
Emperor Taishō
The was the 123rd emperor of Japan, according to the traditional order of succession, reigning from 30 July 1912, until his death in 1926.The Emperor’s personal name was . According to Japanese customs, the emperor has no name during his reign and is only called the Emperor...
in 1926. The repetition of the formal announcement provided GCCS with cribs
Known-plaintext attack
The known-plaintext attack is an attack model for cryptanalysis where the attacker has samples of both the plaintext , and its encrypted version . These can be used to reveal further secret information such as secret keys and code books...
into almost every code in use. Later in 1934, Foss was able to break an early Japanese cipher machine.
Tiltman provided the major break into JN25 in 1939.
In early 1942, decrypts from Anderson gave advance warning of Vice Admiral Nagumo
Chuichi Nagumo
was a Japanese admiral in the Imperial Japanese Navy during World War II and one time commander of the Kido Butai . He committed suicide during the Battle of Saipan.-Early life:...
's Indian Ocean raid
Indian Ocean raid
The Indian Ocean raid was a naval sortie by the Fast Carrier Strike Force of the Imperial Japanese Navy from 31 March-10 April 1942 against Allied shipping and bases in the Indian Ocean. It was an early engagement of the Pacific campaign of World War II...
including a planned attack on Colombo. The warning allowed the British to limit damage, improve opposition, and evacuate the fleet and the cryptanalysts from Colombo to Kilindini.
In May 1945, the team at HMS Anderson successfully broke a message in JN25 that provided details of a supply convoy going from Singapore to the Andaman Islands. This message provided details that led to the sinking of the Japanese cruiser Haguro
Japanese cruiser Haguro
|-External reference links: -External links:**...
in the Battle of the Malacca Strait.
List of Hut 7 personnel
The following people served in Hut 7, HMS Anderson, and Kilindini:- Sidney Abramson, translator at Anderson
- Brian Augarde, mathematician, sub-section chief at Bletchley, worked on JN11
- Peter Barnett, translator at Anderson
- Lieutenant-Commander Barnham, translator at Kilindini
- Charles BawdenCharles BawdenCharles Roskelly Bawden is Emeritus Professor of Mongolian in the University of London.From 1955 to 1984, he was a Lecturer, Reader, and Professor of Mongolian at the School of Oriental and African Studies at the University of London....
, linguist at Anderson - Ted Biggs, ex-diplomat, Kilindini, Anderson, and Melbourne
- Gerry Brennan, cryptanalyst at Bletchley, worked on JN40
- Leo Brouwer, Lieutenant-Commander RNN; a Japanese linguist from Kamer 14 (Java); Colombo, Kilindini, Hut 7
- Maurice Burnett, linguist at Anderson
- John Catlow, linguist at Anderson
- Dudley Cheke, Kilindini
- Jon Cohen, linguist/cryptanalyst temporarily assigned to Diplomatic Section, later to Bletchley, and Kilindini
- Lieutenant-Commander E.H. Colgrave
- George Curnock, translator at Anderson and Kilindini
- Wynn Davies, translator/cryptanalyst at Bletchley and Kilindini
- Denny Denham, translator at Anderson
- Hugh Denham, cryptanalyst at Bletchley, Kilindini, and Anderson, worked on JN25
- Alan Douglas, linguist temporarily assigned to Diplomatic Section
- John English, sub-section chief at Bletchley
- Harry Field, Anderson
- Forman, Kilindini
- Hugh FossHugh FossHugh Rose Foss was a British cryptographer.-Life:Foss was born in Kobe, Japan, where his father the Rt Revd Hugh Foss was a missionary bishop, and he learned Japanese....
, head of Hut 7 - Sergeant Harris-Jones, assistant translator at Bletchley
- Hubert Eustace Hooper, linguist at Anderson
- George Hunter, linguist at Anderson
- Hayden John, cryptanalyst, ran JN40 group at Bletchley
- Lieutenant-Commander Bruce Keith, translator at Bletchley
- Johnnie Lambert, cryptanalyst at Bletchley and Anderson
- Peter LaslettPeter Laslett-Biography:Born Thomas Peter Ruffell Laslett and educated at the Watford Grammar School for Boys, Peter Laslett studied history at St John's College, Cambridge in 1935 and graduated with a double first in 1938. During the war he learned Japanese and worked at Bletchley Park and Washington decoding...
, cryptanalyst at Bletchley, worked on JN11 - Peter Lawrence, translator at Anderson
- John Lloyd, language instructor at Bletchley
- Michael LoeweMichael LoeweMichael Loewe , also known as M. A. N. Loewe, is a British academic and renowned sinologist who has authored dozens of books, articles, and other publications in the fields of Classical Chinese and ancient Chinese history....
, linguist/cryptanalyst at Bletchley and Kilindini - John MacInnes, cryptanalyst at Kilindini
- Commander McIntyre RN, translator, at Kilindini and ran JN25 group at Bletchley
- Alan Merry, translator at Melbourne, Kilindini, and ran JN40 group at Anderson
- Milner, support at Anderson
- George Mitchell, Anderson
- Sandy Morris, Anderson
- Nichol, translator at Bletchley
- Commander Parsons RN, translator at Kilindini
- Jimmy Pollard, cryptanalyst at Bletchley, worked on JN40
- Pond, support at Anderson
- Fred Ponting, cryptanalyst at Bletchley, worked on JN11
- Norman Scott, mathematician / cryptanalyst at Bletchley and Anderson, worked on JN11 and JN25
- John Sharman, cryptanalyst at Anderson and Kilindini
- John SilkinJohn SilkinJohn Ernest Silkin, PC was an English Labour politician and solicitor.He was the third son of Lewis Silkin, 1st Baron Silkin, and a younger brother of Samuel Silkin, Baron Silkin of Dulwich. He was educated at Dulwich College, the University of Wales, and Trinity Hall at the University of...
, linguist at Anderson - Stanton, cryptanalyst at Kilindini
- John Sutcliffe, cryptanalyst at Bletchley
- Patrick Taylor, mathematician at Bletchley
- Wilf Taylor, linguist at Anderson
- Captain Dick Thatcher RN, worked on JN 25 at Bletchley, was at FECB Hong Kong
- Brian Townend, cryptanalyst at Kilindini, contributed a break into JN40
- Richard Wolfe, Anderson
- Leslie YoxallLeslie YoxallAlbert Leslie Yoxall was a British codebreaker at Bletchley Park during World War II. He devised a method to assist in solving Enigma messages which was dubbed Yoxallismus. After the war he worked at GCHQ until the mid-1970s.-Early life:Yoxall was born in Salford, and was the youngest out of four...
, cryptanalyst at Bletchley, previously working in Hut 8