Bletchley Park is a nineteenth-century mansion and estate near Milton Keynes in Buckinghamshire, constructed during the years following 1883 for the English financier and politician Sir Herbert Samuel Leon in the Victorian Gothic, Tudor, and Dutch Baroque styles, on the site of older buildings of the same name. It has received latter-day fame as the central site for British (and subsequently, Allied) codebreakers during World War II, although at the time of their operation this fact was a closely guarded secret. During the Second World War, the estate housed the British Government Code and Cypher School (GC&CS), which regularly penetrated the secret communications of the Axis Powers – most importantly the German Enigma and Lorenz ciphers; among its most notable early personnel the GC&CS team of codebreakers included Alan Turing, Gordon Welchman, Hugh Alexander and Stuart Milner-Barry.
According to the official historian of British Intelligence, the "Ultra" intelligence produced at Bletchley shortened the war by two to four years, and without it the outcome of the war would have been uncertain. The team at Bletchley Park devised automatic machinery to help with decryption, culminating in the development of Colossus, the world's first programmable digital electronic computer.[a] Codebreaking operations at Bletchley Park came to an end in 1946 and all information about the wartime operations was classified until the mid 1970s. After the war, the Post Office took over the site and used it as a management school, but by 1990 the huts in which the codebreakers worked were being considered for demolition and redevelopment, and the Bletchley Park Trust formed in 1991 to save large portions of the site from developers. More recently, Bletchley Park has been open to the public and houses interpretive exhibits and rebuilt huts as they would have appeared during their wartime operations, as well as The National Museum of Computing, established on the site which includes a rebuilt Colossus machine, and receives hundreds of thousands of visitors annually.
The Mansion in 2017
Location in Buckinghamshire
|Established||1938 (as a code-breaking centre); 1993 (as a museum)|
|Location||Bletchley, Milton Keynes, Buckinghamshire, England, United Kingdom|
|Public transit access||Bletchley railway station|
The site appears in the Domesday Book as part of the Manor of Eaton. Browne Willis built a mansion there in 1711, but after Thomas Harrison purchased the property in 1793 this was pulled down. It was first known as Bletchley Park after its purchase by Samuel Lipscomb Seckham in 1877. The estate of 581 acres (235 ha) was bought in 1883 by Sir Herbert Samuel Leon, who expanded the then-existing farmhouse into what architect Landis Gores called a "maudlin and monstrous pile" combining Victorian Gothic, Tudor, and Dutch Baroque styles. At his Christmas family gatherings there was a horse meet on Boxing Day with glasses of sloe gin from the butler, and the house was always "humming with servants". With 40 gardeners, a flower bed of yellow daffodils could become a sea of red tulips overnight.
In 1938, the mansion and much of the site was bought by a builder for a housing estate, but in May 1938 Admiral Sir Hugh Sinclair, head of the Secret Intelligence Service (SIS or MI6), bought the mansion and 58 acres (23 ha) of land for £6,000 (£376,000 today), using his own money after the Government said they did not have the budget to do so, for use by GC&CS and SIS in the event of war.
A key advantage seen by Sinclair and his colleagues (inspecting the site under the cover of "Captain Ridley's shooting party") was Bletchley's geographical centrality. It was almost immediately adjacent to Bletchley railway station, where the "Varsity Line" between Oxford and Cambridge – whose universities were expected to supply many of the code-breakers – met the main West Coast railway line connecting London, Birmingham, Manchester, Liverpool, Glasgow and Edinburgh. Watling Street, the main road linking London to the north-west (subsequently the A5) was close by, and high-volume communication links were available at the telegraph and telephone repeater station in nearby Fenny Stratford.
Bletchley Park was known as "B.P." to those who worked there. "Station X" (X = Roman numeral ten), "London Signals Intelligence Centre", and "Government Communications Headquarters" were all cover names used during the war. The formal posting of the many "Wrens" – members of the Women's Royal Naval Service – working there, was to HMS Pembroke V. Royal Air Force names of Bletchley Park and its outstations included RAF Eastcote, RAF Lime Grove and RAF Church Green. The postal address that staff had to use was "Room 47, Foreign Office".
After the war, the Government Code & Cypher School became the Government Communications Headquarters (GCHQ), moving to Eastcote in 1946 and to Cheltenham in the 1950s. The site was used by various government agencies, including the GPO and the Civil Aviation Authority. One large building, block F, was demolished in 1987 by which time the site was being run down with tenants leaving. In 1990 the site was at risk of being sold for housing development. However, Milton Keynes Council made it into a conservation area. Bletchley Park Trust was set up in 1991 by a group of people who recognised the site's importance. The initial trustees included Roger Bristow, Ted Enever, Peter Wescombe, Dr Peter Jarvis of the Bletchley Archaeological & Historical Society, and Tony Sale who in 1994 became the first director of the Bletchley Park Museums.
Commander Alastair Denniston was operational head of GC&CS from 1919 to 1942, beginning with its formation from the Admiralty's Room 40 (NID25) and the War Office's MI1b. Key GC&CS cryptanalysts who moved from London to Bletchley Park included John Tiltman, Dillwyn "Dilly" Knox, Josh Cooper, and Nigel de Grey. These people had a variety of backgrounds – linguists and chess champions were common, and in Knox's case papyrology. The British War Office recruited top solvers of cryptic crossword puzzles, as these individuals had strong lateral thinking skills.
On the day Britain declared war on Germany, Denniston wrote to the Foreign Office about recruiting "men of the professor type". Personal networking drove early recruitments, particularly of men from the universities of Cambridge and Oxford. Trustworthy women were similarly recruited for administrative and clerical jobs. In one 1941 recruiting stratagem, The Daily Telegraph was asked to organise a crossword competition, after which promising contestants were discreetly approached about "a particular type of work as a contribution to the war effort".
Denniston recognised, however, that the enemy's use of electromechanical cipher machines meant that formally trained mathematicians would also be needed; Oxford's Peter Twinn joined GC&CS in February 1939; Cambridge's Alan Turing and Gordon Welchman began training in 1938 and reported to Bletchley the day after war was declared, along with John Jeffreys. Later-recruited cryptanalysts included the mathematicians Derek Taunt, Jack Good, Bill Tutte, and Max Newman; historian Harry Hinsley, and chess champions Hugh Alexander and Stuart Milner-Barry. Joan Clarke (eventually deputy head of Hut 8) was one of the few women employed at Bletchley as a full-fledged cryptanalyst.
This eclectic staff of "Boffins and Debs" (scientists and debutantes, young women of high society) caused GC&CS to be whimsically dubbed the "Golf, Cheese and Chess Society". During a September 1941 morale-boosting visit, Winston Churchill reportedly remarked to Denniston: "I told you to leave no stone unturned to get staff, but I had no idea you had taken me so literally." Six weeks later, having failed to get sufficient typing and unskilled staff to achieve the productivity that was possible, Turing, Welchman, Alexander and Milner-Barry wrote directly to Churchill. His response was "Action this day make sure they have all they want on extreme priority and report to me that this has been done."  The Army CIGS Alan Brooke wrote that on 16 April 1942 "Took lunch in car and went to see the organization for breaking down ciphers – a wonderful set of professors and genii! I marvel at the work they succeed in doing." 
After initial training at the Inter-Service Special Intelligence School set up by John Tiltman (initially at an RAF depot in Buckingham and later in Bedford – where it was known locally as "the Spy School") staff worked a six-day week, rotating through three shifts: 4 p.m. to midnight, midnight to 8 a.m. (the most disliked shift), and 8 a.m. to 4 p.m., each with a half-hour meal break. At the end of the third week, a worker went off at 8 a.m. and came back at 4 p.m., thus putting in sixteen hours on that last day. The irregular hours affected workers' health and social life, as well as the routines of the nearby homes at which most staff lodged. The work was tedious and demanded intense concentration; staff got one week's leave four times a year, but some "girls" collapsed and required extended rest. Recruitment took place to combat a shortage of experts in Morse code and German.
In January 1945, at the peak of codebreaking efforts, some 10,000 personnel were working at Bletchley and its outstations. About three-quarters of these  were women. Many of the women came from middle-class backgrounds and held degrees in the areas of mathematics, physics and engineering; they were given entry into STEM programs due to the lack of men, who had been sent to war. They performed complex calculations and coding and hence were integral to the computing processes. For example, Eleanor Ireland worked on the Colossus computers.
The female staff in Dilwyn Knox's section were sometimes termed "Dilly's Fillies". "Dilly's girls" included Jean Perrin, Clare Harding, Rachel Ronald, and Elisabeth Granger. Jane Hughes processed information leading to the last battle of the Bismarck. Mavis Lever (who married mathematician and fellow code-breaker Keith Batey) made the first break into the Italian naval traffic. She and Margaret Rock solved a German code, the Abwehr break.
Many of the women had backgrounds in languages, particularly French and German. Rozanne Colchester was a translator who worked at Bletchley from April 1942 until January 1945, mainly for the Italian air forces Section. Like most of the 'Bletchleyettes', she came from the higher middle class, her father, Air Vice-Marshal Sir Charles Medhurst, being an air attaché in Rome. Before joining Bletchley, Colchester was moving in high circles: “she had met Hitler and been flirted with by Mussolini at an embassy party”, writes Sarah Rainey. She joined the Park because she found it thrilling to fight for her country.
Cicely Mayhew was recruited straight from university, having graduated from Lady Margaret Hall, Oxford in 1944 with a First in French and German, after only two years. She worked in Hut 8, translating decoded German Navy signals.
For a long time, the British Government didn't recognize the contributions the personnel at Bletchley Park made. Their work achieved official recognition only in 2009.
Properly used, the German Enigma and Lorenz ciphers should have been virtually unbreakable, but flaws in German cryptographic procedures, and poor discipline among the personnel carrying them out, created vulnerabilities that made Bletchley's attacks just barely feasible. These vulnerabilities, however, could have been remedied by relatively simple improvements in enemy procedures, and such changes would certainly have been implemented had Germany had any hint of Bletchley's success. Thus the intelligence Bletchley produced was considered wartime Britain's "Ultra secret" – higher even than the normally highest classification Most Secret – and security was paramount.
All staff signed the Official Secrets Act (1939) and a 1942 security warning emphasised the importance of discretion even within Bletchley itself: "Do not talk at meals. Do not talk in the transport. Do not talk travelling. Do not talk in the billet. Do not talk by your own fireside. Be careful even in your Hut ..."
Nevertheless, there were security leaks. Jock Colville, the Assistant Private Secretary to Winston Churchill, recorded in his diary on 31 July 1941, that the newspaper proprietor Lord Camrose had discovered Ultra and that security leaks "increase in number and seriousness". Without doubt, the most serious of these was that Bletchley Park had been infiltrated by John Cairncross, the notorious Soviet mole and member of the Cambridge Spy Ring, who leaked Ultra material to Moscow.
The first personnel of the Government Code and Cypher School (GC&CS) moved to Bletchley Park on 15 August 1939. The Naval, Military, and Air Sections were on the ground floor of the mansion, together with a telephone exchange, teleprinter room, kitchen, and dining room; the top floor was allocated to MI6. Construction of the wooden huts began in late 1939, and Elmers School, a neighbouring boys' boarding school in a Victorian Gothic redbrick building by a church, was acquired for the Commercial and Diplomatic Sections.
After the United States joined World War II, a number of American cryptographers were posted to Hut 3, and from May 1943 onwards there was close co-operation between British and American intelligence. (See 1943 BRUSA Agreement.) In contrast, the Soviet Union was never officially told of Bletchley Park and its activities – a reflection of Churchill's distrust of the Soviets even during the US-UK-USSR alliance imposed by the Nazi threat.
The only direct enemy damage to the site was done 20–21 November 1940 by three bombs probably intended for Bletchley railway station; Hut 4, shifted two feet off its foundation, was winched back into place as work inside continued.
Non-naval Enigma messages were deciphered in Hut 6, followed by translation, indexing and cross-referencing, in Hut 3. Only then was it sent out to the Secret Intelligence Service (MI6), the intelligence chiefs in the relevant ministries, and later on to high-level commanders in the field.
Naval Enigma deciphering was in Hut 8, with translation in Hut 4. Verbatim translations were sent only to the Naval Intelligence Division (NID) of the Admiralty's Operational Intelligence Centre (OIC), supplemented by information from indexes as to the meaning of technical terms and cross-references from a knowledge store of German naval technology.
Hut 4 also decoded a manual system known as the dockyard cipher, which sometimes carried messages that were also sent on an Enigma network. Feeding these back to Hut 8 provided excellent "cribs" for Known-plaintext attacks on the daily naval Enigma key.
Initially, a wireless room was established at Bletchley Park. It was set up in the mansion's water tower under the code name "Station X", a term now sometimes applied to the codebreaking efforts at Bletchley as a whole. The "X" is the Roman numeral "ten", this being the Secret Intelligence Service's tenth such station. Due to the long radio aerials stretching from the wireless room, the radio station was moved from Bletchley Park to nearby Whaddon Hall to avoid drawing attention to the site.
Subsequently, other listening stations – the Y-stations, such as the ones at Chicksands in Bedfordshire, Beaumanor Hall, Leicestershire (where the headquarters of the War Office "Y" Group was located) and Beeston Hill Y Station in Norfolk – gathered raw signals for processing at Bletchley. Coded messages were taken down by hand and sent to Bletchley on paper by motorcycle despatch riders or (later) by teleprinter.
The wartime needs required the building of additional accommodation.
Often a hut's number became so strongly associated with the work performed inside that even when the work was moved to another building it was still referred to by the original "Hut" designation.
In addition to the wooden huts, there were a number of brick-built "blocks".
Most German messages decrypted at Bletchley were produced by one or another version of the Enigma cipher machine, but an important minority were produced by the even more complicated twelve-rotor Lorenz SZ42 on-line teleprinter cipher machine.
Five weeks before the outbreak of war, Warsaw's Cipher Bureau revealed its achievements in breaking Enigma to astonished French and British personnel. The British used the Poles' information and techniques, and the Enigma clone sent to them in August 1939, which greatly increased their (previously very limited) success in decrypting Enigma messages.
The bombe was an electromechanical device whose function was to discover some of the daily settings of the Enigma machines on the various German military networks. Its pioneering design was developed by Alan Turing (with an important contribution from Gordon Welchman) and the machine was engineered by Harold 'Doc' Keen of the British Tabulating Machine Company. Each machine was about 7 feet (2.1 m) high and wide, 2 feet (0.61 m) deep and weighed about a ton.
At its peak, GC&CS was reading approximately 4,000 messages per day. As a hedge against enemy attack most bombes were dispersed to installations at Adstock and Wavendon (both later supplanted by installations at Stanmore and Eastcote), and Gayhurst.
Luftwaffe messages were the first to be read in quantity. The German navy had much tighter procedures, and the capture of code books was needed before they could be broken. When, in February 1942, the German navy introduced the four-rotor Enigma for communications with its Atlantic U-boats, this traffic became unreadable for a period of ten months. Britain produced modified bombes, but it was the success of the US Navy bombe that was the main source of reading messages from this version of Enigma for the rest of the war. Messages were sent to and fro across the Atlantic by enciphered teleprinter links.
The Lorenz messages were codenamed Tunny at Bletchley Park. They were only sent in quantity from mid-1942. The Tunny networks were used for high-level messages between German High Command and field commanders. With the help of German operator errors, the cryptanalysts in the Testery (named after Ralph Tester, its head) worked out the logical structure of the machine despite not knowing its physical form. They devised automatic machinery to help with decryption, which culminated in Colossus, the world's first programmable digital electronic computer. This was designed and built by Tommy Flowers and his team at the Post Office Research Station at Dollis Hill. The prototype first worked in December 1943, was delivered to Bletchley Park in January and first worked operationally on 5 February 1944. Enhancements were developed for the Mark 2 Colossus, the first of which was working at Bletchley Park on the morning of 1 June in time for D-day. Flowers then produced one Colossus a month for the rest of the war, making a total of ten with an eleventh part-built. The machines were operated mainly by Wrens in a section named the Newmanry after its head Max Newman.
Bletchley's work was essential to defeating the U-boats in the Battle of the Atlantic, and to the British naval victories in the Battle of Cape Matapan and the Battle of North Cape. In 1941, Ultra exerted a powerful effect on the North African desert campaign against German forces under General Erwin Rommel. General Sir Claude Auchinleck wrote that were it not for Ultra, "Rommel would have certainly got through to Cairo". While not changing the events, "Ultra" decrypts featured prominently in the story of Operation SALAM, László Almásy's mission across the desert behind Allied lines in 1942. Prior to the Normandy landings on D-Day in June 1944, the Allies knew the locations of all but two of Germany's fifty-eight Western-front divisions.
Italian signals had been of interest since Italy's attack on Abyssinia in 1935. During the Spanish Civil War the Italian Navy used the K model of the commercial Enigma without a plugboard; this was solved by Knox in 1937. When Italy entered the war in 1940 an improved version of the machine was used, though little traffic was sent by it and there were "wholesale changes" in Italian codes and cyphers.
Knox was given a new section for work on Enigma variations, which he staffed with women ("Dilly's girls"), who included Margaret Rock, Jean Perrin, Clare Harding, Rachel Ronald, Elisabeth Granger; and Mavis Lever. Mavis Lever solved the signals revealing the Italian Navy's operational plans before the Battle of Cape Matapan in 1941, leading to a British victory.
On entering World War II in June 1940, the Italians were using book codes for most of their military messages. The exception was the Italian Navy, which after the Battle of Cape Matapan started using the C-38 version of the Boris Hagelin rotor-based cipher machine, particularly to route their navy and merchant marine convoys to the conflict in North Africa. As a consequence, JRM Butler recruited his former student Bernard Willson to join a team with two others in Hut 4. In June 1941, Willson became the first of the team to decode the Hagelin system, thus enabling military commanders to direct the Royal Navy and Royal Air Force to sink enemy ships carrying supplies from Europe to Rommel's Afrika Korps. This led to increased shipping losses and, from reading the intercepted traffic, the team learnt that between May and September 1941 the stock of fuel for the Luftwaffe in North Africa reduced by 90 percent. After an intensive language course, in March 1944 Willson switched to Japanese language-based codes.
A Middle East Intelligence Centre (MEIC) was set up in Cairo in 1939. When Italy entered the war in June 1940, delays in forwarding intercepts to Bletchley via congested radio links resulted in cryptanalysts being sent to Cairo. A Combined Bureau Middle East (CBME) was set up in November, though the Middle East authorities made "increasingly bitter complaints" that GC&CS was giving too little priority to work on Italian cyphers. However, the principle of concentrating high-grade cryptanalysis at Bletchley was maintained. John Chadwick started cryptanalysis work in 1942 on Italian signals at the naval base 'HMS Nile' in Alexandria. Later, he was with GC&CS; in the Heliopolis Museum, Cairo and then in the Villa Laurens, Alexandria.
Soviet signals had been studied since the 1920s. In 1939–40, John Tiltman (who had worked on Russian Army traffic from 1930) set up two Russian sections at Wavendon (a country house near Bletchley) and at Sarafand in Palestine. Two Russian high-grade army and navy systems were broken early in 1940. Tiltman spent two weeks in Finland, where he obtained Russian traffic from Finland and Estonia in exchange for radio equipment. In June 1941, when the Soviet Union became an ally, Churchill ordered a halt to intelligence operations against it. In December 1941, the Russian section was closed down, but in late summer 1943 or late 1944, a small GC&CS Russian cypher section was set up in London overlooking Park Lane, then in Sloane Square.
An outpost of the Government Code and Cypher School had been set up in Hong Kong in 1935, the Far East Combined Bureau (FECB). The FECB naval staff moved in 1940 to Singapore, then Colombo, Ceylon, then Kilindini, Mombasa, Kenya. They succeeded in deciphering Japanese codes with a mixture of skill and good fortune. The Army and Air Force staff went from Singapore to the Wireless Experimental Centre at Delhi, India.
In early 1942, a six-month crash course in Japanese, for 20 undergraduates from Oxford and Cambridge, was started by the Inter-Services Special Intelligence School in Bedford, in a building across from the main Post Office. This course was repeated every six months until war's end. Most of those completing these courses worked on decoding Japanese naval messages in Hut 7, under John Tiltman.
By mid-1945, well over 100 personnel were involved with this operation, which co-operated closely with the FECB and the US Signal intelligence Service at Arlington Hall, Virginia. In 1999, Michael Smith wrote that: "Only now are the British codebreakers (like John Tiltman, Hugh Foss, and Eric Nave) beginning to receive the recognition they deserve for breaking Japanese codes and cyphers".
After the War, the secrecy imposed on Bletchley staff remained in force, so that most relatives never knew more than that a child, spouse, or parent had done some kind of secret war work. Churchill referred to the Bletchley staff as "the geese that laid the golden eggs and never cackled". That said, occasional mentions of the work performed at Bletchley Park slipped the censor's net and appeared in print.
With the publication of F. W. Winterbotham's The Ultra Secret (1974) public discussion of Bletchley's work finally became possible (though even today some former staff still consider themselves bound to silence) and in July 2009 the British government announced that Bletchley personnel would be recognised with a commemorative badge.
After the war, the site passed through a succession of hands and saw a number of uses, including as a teacher-training college and local GPO headquarters. By 1991, the site was nearly empty and the buildings were at risk of demolition for redevelopment.
In February 1992, the Milton Keynes Borough Council declared most of the Park a conservation area, and the Bletchley Park Trust was formed to maintain the site as a museum. The site opened to visitors in 1993, and was formally inaugurated by HRH The Duke of Kent as Chief Patron in July 1994. In 1999 the land owners, the Property Advisors to the Civil Estate and BT, granted a lease to the Trust giving it control over most of the site.
June 2014 saw the completion of an £8 million restoration project, which was marked by a visit from Catherine, Duchess of Cambridge. The Duchess' paternal grandmother, Valerie, and Valerie's twin sister, Mary (née Glassborow), both worked at Bletchley Park during the war. The twin sisters worked as Foreign Office Civilians in Hut 6, where they managed the interception of enemy and neutral diplomatic signals for decryption. Valerie married Catherine's grandfather, Captain Peter Middleton. A memorial at Bletchley Park commemorates Mary and Valerie Middleton's work as code-breakers.
The Bletchley Park Learning Department offers educational group visits with active learning activities for schools and universities. Visits can be booked in advance during term time, where students can engage with the history of Bletchley Park and understand its wider relevance for computer history and national security. Their workshops cover introductions to codebreaking, cyber security and the story of Enigma and Lorenz.
In October 2005, American billionaire Sidney Frank donated £500,000 to Bletchley Park Trust to fund a new Science Centre dedicated to Alan Turing. Simon Greenish joined as Director in 2006 to lead the fund-raising effort in a post he held until 2012 when Iain Standen took over the leadership role. In July 2008, a letter to The Times from more than a hundred academics condemned the neglect of the site. In September 2008, PGP, IBM, and other technology firms announced a fund-raising campaign to repair the facility. On 6 November 2008 it was announced that English Heritage would donate £300,000 to help maintain the buildings at Bletchley Park, and that they were in discussions regarding the donation of a further £600,000.
In October 2011, the Bletchley Park Trust received a £4.6m Heritage Lottery Fund grant to be used "to complete the restoration of the site, and to tell its story to the highest modern standards" on the condition that £1.7m of 'match funding' is raised by the Bletchley Park Trust. Just weeks later, Google contributed £550k and by June 2012 the trust had successfully raised £2.4m to unlock the grants to restore Huts 3 and 6, as well as develop its exhibition centre in Block C.
The National Museum of Computing is housed in Block H, which is rented from the Bletchley Park Trust. Its Colossus and Tunny galleries tell an important part of allied breaking of German codes during World War II. There is a working reconstruction of a Bombe and a rebuilt Colossus computer which was used on the high-level Lorenz cipher, codenamed Tunny by the British.
The museum, which opened in 2007, is an independent voluntary organisation that is governed by its own board of trustees. Its aim is "To collect and restore computer systems particularly those developed in Britain and to enable people to explore that collection for inspiration, learning and enjoyment." Through its many exhibits, the museum displays the story of computing through the mainframes of the 1960s and 1970s, and the rise of personal computing in the 1980s. It has a policy of having as many of the exhibits as possible in full working order.
This consists of serviced office accommodation housed in Bletchley Park’s Blocks A and E, and the upper floors of the Mansion. Its aim is to foster the growth and development of dynamic knowledge-based start-ups and other businesses.
The National Museum of Computing is working with four other organisations – but not Bletchley Park Trust – in a group called Qufaro, to create the National College of Cyber Security. This will be for students between 16 and 19 years of age. It will be located in Block G which is being renovated with funding from the Bletchley Park Science and Innovation Centre.
The Radio Society of Great Britain's National Radio Centre (including a library, radio station, museum and bookshop) are in a newly constructed building close to the main Bletchley Park entrance.
The 37-year-old opened up as she visited the estate near Milton Keynes on Tuesday to see a new exhibition celebrating the role codebreakers played in the D-Day landings almost 75 years ago....she was shown a memorial containing the name of her father’s mother and great-aunt, who also worked at Bletchley.
Alan Mathison Turing (; 23 June 1912 – 7 June 1954) was an English mathematician, computer scientist, logician, cryptanalyst, philosopher and theoretical biologist. Turing was highly influential in the development of theoretical computer science, providing a formalisation of the concepts of algorithm and computation with the Turing machine, which can be considered a model of a general-purpose computer. Turing is widely considered to be the father of theoretical computer science and artificial intelligence. Despite these accomplishments, he was not fully recognised in his home country during his lifetime, due to his homosexuality, and because much of his work was covered by the Official Secrets Act.
During the Second World War, Turing worked for the Government Code and Cypher School (GC&CS) at Bletchley Park, Britain's codebreaking centre that produced Ultra intelligence. For a time he led Hut 8, the section that was responsible for German naval cryptanalysis. Here, he devised a number of techniques for speeding the breaking of German ciphers, including improvements to the pre-war Polish bombe method, an electromechanical machine that could find settings for the Enigma machine.
Turing played a pivotal role in cracking intercepted coded messages that enabled the Allies to defeat the Nazis in many crucial engagements, including the Battle of the Atlantic, and in so doing helped win the war. Due to the problems of counterfactual history, it's hard to estimate what effect Ultra intelligence had on the war, but at the upper end it has been estimated that this work shortened the war in Europe by more than two years and saved over 14 million lives.After the war, Turing worked at the National Physical Laboratory, where he designed the Automatic Computing Engine, which was one of the first designs for a stored-program computer. In 1948, Turing joined Max Newman's Computing Machine Laboratory at the Victoria University of Manchester, where he helped develop the Manchester computers and became interested in mathematical biology. He wrote a paper on the chemical basis of morphogenesis and predicted oscillating chemical reactions such as the Belousov–Zhabotinsky reaction, first observed in the 1960s.
Turing was prosecuted in 1952 for homosexual acts; the Labouchere Amendment of 1885 had mandated that "gross indecency" was a criminal offence in the UK. He accepted chemical castration treatment, with DES, as an alternative to prison. Turing died in 1954, 16 days before his 42nd birthday, from cyanide poisoning. An inquest determined his death as a suicide, but it has been noted that the known evidence is also consistent with accidental poisoning.
In 2009, following an Internet campaign, British Prime Minister Gordon Brown made an official public apology on behalf of the British government for "the appalling way he was treated". Queen Elizabeth II granted Turing a posthumous pardon in 2013. The Alan Turing law is now an informal term for a 2017 law in the United Kingdom that retroactively pardoned men cautioned or convicted under historical legislation that outlawed homosexual acts.On 15 July 2019 the Bank of England announced that Turing would be depicted on the United Kingdom's new £50 note.Battle of Cape Matapan
The Battle of Cape Matapan (Greek: Ναυμαχία του Ταινάρου) was a Second World War naval engagement between British Imperial and Axis forces, fought from 27–29 March 1941. The cape is on the south-west coast of the Peloponnesian peninsula of Greece. Following the interception of Italian signals by the Government Code and Cypher School (GC&CS) at Bletchley Park, ships of the Royal Navy and Royal Australian Navy, under the command of the Royal Navy's Admiral Sir Andrew Cunningham, intercepted and sank or severely damaged several ships of the Italian Regia Marina under Squadron-Vice-Admiral Angelo Iachino. The opening actions of the battle are also known in Italy as the Battle of Gaudo.Bletchley
Bletchley is a constituent town of Milton Keynes, in the ceremonial county of Buckinghamshire, England. It is situated in the south-west of Milton Keynes, and is split between the civil parishes of Bletchley and Fenny Stratford and West Bletchley.
Bletchley is best known for Bletchley Park, the headquarters of Britain's World War II codebreaking organisation, and now a major tourist attraction. The National Museum of Computing is also located on the Park.Colossus computer
Colossus was a set of computers developed by British codebreakers in the years 1943–1945 to help in the cryptanalysis of the Lorenz cipher. Colossus used thermionic valves (vacuum tubes) to perform Boolean and counting operations. Colossus is thus regarded as the world's first programmable, electronic, digital computer, although it was programmed by switches and plugs and not by a stored program.Colossus was designed by research telephone engineer Tommy Flowers to solve a problem posed by mathematician Max Newman at the Government Code and Cypher School (GC&CS) at Bletchley Park. Alan Turing's use of probability in cryptanalysis (see Banburismus) contributed to its design. It has sometimes been erroneously stated that Turing designed Colossus to aid the cryptanalysis of the Enigma. Turing's machine that helped decode Enigma was the electromechanical Bombe, not Colossus.The prototype, Colossus Mark 1, was shown to be working in December 1943 and was in use at Bletchley Park by early 1944. An improved Colossus Mark 2 that used shift registers to quintuple the processing speed, first worked on 1 June 1944, just in time for the Normandy landings on D-Day. Ten Colossi were in use by the end of the war and an eleventh was being commissioned. Bletchley Park's use of these machines allowed the Allies to obtain a vast amount of high-level military intelligence from intercepted radiotelegraphy messages between the German High Command (OKW) and their army commands throughout occupied Europe.
The existence of the Colossus machines was kept secret until the mid-1970s; the machines and the plans for building them had previously been destroyed in the 1960s as part of the effort to maintain the secrecy of the project. This deprived most of those involved with Colossus of the credit for pioneering electronic digital computing during their lifetimes. A functioning rebuild of a Mark 2 Colossus was completed in 2008 by Tony Sale and some volunteers; it is on display at The National Museum of Computing at Bletchley Park.Conel Hugh O'Donel Alexander
Conel Hugh O'Donel Alexander (19 April 1909 – 15 February 1974), known as Hugh Alexander and C. H. O'D. Alexander as a pen name, was an Irish-born British cryptanalyst, chess player, and chess writer. He worked on the German Enigma machine at Bletchley Park during the Second World War, and was later the head of the cryptanalysis division at GCHQ for 25 years. In chess, he was twice British chess champion and earned the title of International Master.Cryptanalysis of the Enigma
Cryptanalysis of the Enigma ciphering system enabled the western Allies in World War II to read substantial amounts of Morse-coded radio communications of the Axis powers that had been enciphered using Enigma machines. This yielded military intelligence which, along with that from other decrypted Axis radio and teleprinter transmissions, was given the codename Ultra. This was considered by western Supreme Allied Commander Dwight D. Eisenhower to have been "decisive" to the Allied victory.The Enigma machines were a family of portable cipher machines with rotor scramblers. Good operating procedures, properly enforced, would have made the plugboard Enigma machine unbreakable. However, most of the German military forces, secret services and civilian agencies that used Enigma employed poor operating procedures, and it was these poor procedures that allowed the Enigma machines to be reverse-engineered and the ciphers to be read.
The German plugboard-equipped Enigma became Nazi Germany's principal crypto-system. It was broken by the Polish General Staff's Cipher Bureau in December 1932, with the aid of French-supplied intelligence material obtained from a German spy. A month before the outbreak of World War II, at a conference held near Warsaw, the Polish Cipher Bureau shared its Enigma-breaking techniques and technology with the French and British. During the German invasion of Poland, core Polish Cipher Bureau personnel were evacuated, via Romania, to France where they established the PC Bruno signals intelligence station with French facilities support. Successful cooperation among the Poles, the French, and the British at Bletchley Park continued until June 1940, when France surrendered to the Germans.
From this beginning, the British Government Code and Cypher School (GC&CS) at Bletchley Park built up an extensive cryptanalytic capability. Initially, the decryption was mainly of Luftwaffe (German air force) and a few Heer (German army) messages, as the Kriegsmarine (German navy) employed much more secure procedures for using Enigma. Alan Turing, a Cambridge University mathematician and logician, provided much of the original thinking that led to the design of the cryptanalytical bombe machines that were instrumental in eventually breaking the naval Enigma. However, the Kriegsmarine introduced an Enigma version with a fourth rotor for its U-boats, resulting in a prolonged period when these messages could not be decrypted. With the capture of relevant cipher keys and the use of much faster US Navy bombes, regular, rapid reading of U-boat messages resumed.Enigma (2001 film)
Enigma is a 2001 espionage thriller film directed by Michael Apted from a screenplay by Tom Stoppard. The script was adapted from the novel Enigma by Robert Harris, about the Enigma codebreakers of Bletchley Park in the Second World War.
Although the story is highly fictionalised, the process of encrypting German messages during World War II and decrypting them with the Enigma is discussed in detail, and the historical event of the Katyn massacre is highlighted. It was the last film scored by John Barry.Gordon Welchman
William Gordon Welchman (15 June 1906 – 8 October 1985) was an English mathematician, university professor, Second World War codebreaker at Bletchley Park and author. After the war he moved to the US, and later took American citizenship.Harry Golombek
Harry Golombek OBE (1 March 1911 – 7 January 1995), was a British chess grandmaster, chess arbiter, chess author, and wartime codebreaker. He was three times British chess champion, in 1947, 1949, and 1955 and finished second in 1948. He was retrospectively awarded the grandmaster title in 1985.He was born in Lambeth to Polish-Jewish parents. He was the chess correspondent of The Times newspaper from 1945 to 1989, following Stuart Milner-Barry. He was an official of the FIDE, and served as Arbiter for several important events, including the Candidates' Tournament of 1959 in Yugoslavia, and the World Chess Championship match 1963 between Mikhail Botvinnik and Tigran Petrosian. He was also editor of some well-known collections of games such as José Raúl Capablanca's and Réti's, and was a well-respected author. He was editor of British Chess Magazine from 1938 to 1940, and its overseas editor throughout the 1960s and 1970s. Golombek also translated several chess books from Russian into English.
On the outbreak of World War II in September 1939, Golombek was in Buenos Aires, Argentina, competing in the Chess Olympiad for Britain alongside C. H. O'D. Alexander and Stuart Milner-Barry. They immediately returned to the UK, and were soon recruited into Bletchley Park, the wartime codebreaking centre. Golombek worked in Hut 8, the section responsible for solving German Naval Enigma, moving to another section in October/November 1942. After the war he lived at 35 Albion Crescent, Chalfont St Giles. He was unusual among public figures in replying with care to letters from unknown persons, such as young schoolboys, from this address.
Golombek represented England nine times in chess Olympiads. He earned the title of International Master in 1950 and was awarded an Honorary Grandmaster title in 1985. He was the first British player to qualify for an Interzonal tournament.
Golombek studied philology at King's College London, having been a pupil at Wilson's Grammar School, Camberwell. He was appointed OBE in 1966, the first to be so honoured for services to chess.Harry Hinsley
Sir Francis Harry Hinsley OBE (26 November 1918 – 16 February 1998) was an English historian and cryptanalyst. He worked at Bletchley Park during the Second World War and wrote widely on the history of international relations and British Intelligence during the Second World War. He was known as Harry Hinsley.Hut 6
Hut 6 was a wartime section of the Government Code and Cypher School (GC&CS) at Bletchley Park, Buckinghamshire, Britain, tasked with the solution of German Army and Air Force Enigma machine cyphers. Hut 8, by contrast, attacked Naval Enigma. Hut 6 was established at the initiative of Gordon Welchman, and was run initially by Welchman and fellow Cambridge mathematician John Jeffreys.
Welchman's deputy, Stuart Milner-Barry, succeeded Welchman as head of Hut 6 in September 1943, at which point over 450 people were working in the section.Hut 6 was partnered with Hut 3, which handled the translation and intelligence analysis of the raw decrypts provided by Hut 6.Hut 8
Hut 8 was a section in the Government Code and Cypher School (GC&CS) at Bletchley Park (the British World War II codebreaking station) tasked with solving German naval (Kriegsmarine) Enigma messages. The section was led initially by Alan Turing. He was succeeded in November 1942 by his deputy, Hugh Alexander. Patrick Mahon succeeded Alexander in September 1944.Hut 8 was partnered with Hut 4, which handled the translation and intelligence analysis of the raw decrypts provided by Hut 8.
Located initially in one of the original single-story wooden huts, the name "Hut 8" was retained when Huts 3, 6 & 8 moved to a new brick building, Block D, in February 1943.After 2005, the first Hut 8 was restored to its wartime condition, and it now houses the "HMS Petard Exhibition".Joan Clarke
Joan Elisabeth Lowther Murray, MBE (née Clarke; 24 June 1917 – 4 September 1996) was an English cryptanalyst and numismatist best known for her work as a code-breaker at Bletchley Park during the Second World War. Although she did not personally seek the spotlight, her role in the Enigma project that decrypted Nazi Germany's secret communications earned her awards and citations, such as appointment as a Member of the Order of the British Empire (MBE), in 1946.John Cairncross
John Cairncross (25 July 1913 – 8 October 1995) was a Scottish-born British civil servant who became an intelligence officer and spy during the Second World War. As a Soviet double agent, he passed to the Soviet Union the raw Tunny decryptions that influenced the Battle of Kursk. He was alleged to be the fifth member of the Cambridge Five. He is also notable as a translator and writer of non-fiction.Miriam Rothschild
Dame Miriam Louisa Rothschild (5 August 1908 – 20 January 2005) was a British natural scientist and author with contributions to zoology, entomology, and botany.The Imitation Game
The Imitation Game is a 2014 American historical drama film directed by Morten Tyldum and written by Graham Moore, based on the biography Alan Turing: The Enigma by Andrew Hodges. It stars Benedict Cumberbatch as British cryptanalyst Alan Turing, who decrypted German intelligence messages for the British government during the Second World War. Keira Knightley, Matthew Goode, Rory Kinnear, Charles Dance, and Mark Strong also star.
The screenplay topped the annual Black List for best unproduced Hollywood scripts in 2011. The Weinstein Company acquired the film for $7 million in February 2014, the highest amount ever paid for U.S. distribution rights at the European Film Market. It was released theatrically in the United States on 28 November 2014.
The Imitation Game grossed over $233 million worldwide on a $14 million production budget, making it the highest-grossing independent film of 2014. It received eight nominations at the 87th Academy Awards, winning for Best Adapted Screenplay, five nominations in the 72nd Golden Globe Awards, and three nominations at the 21st Screen Actors Guild Awards. It also received nine BAFTA nominations and won the People's Choice Award at the 39th Toronto International Film Festival.
The film was criticised by some for its inaccurate portrayal of historical events and for downplaying Turing's homosexuality. However, the LGBT civil rights advocacy organisation the Human Rights Campaign honoured it for bringing Turing's legacy to a wider audience.The National Museum of Computing
The National Museum of Computing is a museum in the United Kingdom dedicated to collecting and restoring historic computer systems. The museum is based in rented premises at Bletchley Park in Milton Keynes, Buckinghamshire and opened in 2007. The building — Block H — was the first purpose-built computer centre in the world, hosting six Colossus computers by the end of World War II.
The museum houses a rebuilt Mark 2 Colossus computer alongside an exhibition of the most complex code cracking activities performed at the Park, along with examples of machines continuing the history of the development of computing from the 1940s to the present day. The museum has a policy of having as many of the exhibits as possible in full working order.
Although located on the Bletchley Park 'campus', The National Museum of Computing is an entirely separate charity with its own fund raising and separate entrance/ticketing. TNMOC receives no public funding and relies on the generosity of donors and supporters.
The museum is working with four other organisations, in a group called Qufaro, to create the
National College of Cyber Security for students between 16 and 19 years of age. The school will be located in Block G which was set to be renovated in 2017 but has sinced been pushed back to an unspecified date, funded by the Bletchley Park Science and Innovation Centre. (Bletchley Park Trust has no involvement with the college.)Ultra
Ultra was the designation adopted by British military intelligence in June 1941 for wartime signals intelligence obtained by breaking high-level encrypted enemy radio and teleprinter communications at the Government Code and Cypher School (GC&CS) at Bletchley Park. Ultra eventually became the standard designation among the western Allies for all such intelligence. The name arose because the intelligence thus obtained was considered more important than that designated by the highest British security classification then used (Most Secret) and so was regarded as being Ultra secret. Several other cryptonyms had been used for such intelligence.
The code name Boniface was used as a cover name for Ultra. In order to ensure that the successful code-breaking did not become apparent to the Germans, British intelligence created a fictional MI6 master spy, Boniface, who controlled a fictional series of agents throughout Germany. Information obtained through code-breaking was often attributed to the human intelligence from the Boniface network. The U.S. used the codename Magic for its decrypts from Japanese sources including the so-called "Purple" cipher.Much of the German cipher traffic was encrypted on the Enigma machine. Used properly, the German military Enigma would have been virtually unbreakable; in practice, shortcomings in operation allowed it to be broken. The term "Ultra" has often been used almost synonymously with "Enigma decrypts". However, Ultra also encompassed decrypts of the German Lorenz SZ 40/42 machines that were used by the German High Command, and the Hagelin machine.Many observers, at the time and later, regarded Ultra as immensely valuable to the Allies. Winston Churchill was reported to have told King George VI, when presenting to him Stewart Menzies (head of the Secret Intelligence Service and the person who controlled distribution of Ultra decrypts to the government): "It is thanks to the secret weapon of General Menzies, put into use on all the fronts, that we won the war!" F. W. Winterbotham quoted the western Supreme Allied Commander, Dwight D. Eisenhower, at war's end describing Ultra as having been "decisive" to Allied victory. Sir Harry Hinsley, Bletchley Park veteran and official historian of British Intelligence in World War II, made a similar assessment of Ultra, saying that while the Allies would have won the war without it, "the war would have been something like two years longer, perhaps three years longer, possibly four years longer than it was." However, Hinsley and others have emphasized the difficulties of counterfactual history in attempting such conclusions, and some historians, such as Keegan have said the shortening might have been as little as the three months it took the United States to deploy the atomic bomb.The existence of Ultra was kept secret for many years after the war. After it was revealed in the middle 1970s, historians have altered the historiography of World War II. For example, Andrew Roberts, writing in the 21st century, states, "Because he had the invaluable advantage of being able to read [Field Marshall Erwin] Rommel's Enigma communications, [General Bernard] Montgomery knew how short the Germans were of men, ammunition, food and above all fuel. When he put Rommel's picture up in his caravan he wanted to be seen to be almost reading his opponent's mind. In fact he was reading his mail." Over time, Ultra has become embedded in the public consciousness and Bletchley Park has become a significant visitor attraction. As stated by historian Thomas Haigh, "The British code-breaking effort of the Second World War, formerly secret, is now one of the most celebrated aspects of modern British history, an inspiring story in which a free society mobilized its intellectual resources against a terrible enemy."West Bletchley
West Bletchley is a district and civil parish that covers the western part of Bletchley; a constituent town of Milton Keynes in Buckinghamshire, England. The parish includes part of Bletchley which is south of Standing Way (A421),
west of the West Coast Main Line, and north of Water Eaton Brook. (The remainder of Bletchley is combined with Fenny Stratford to form the parish of Bletchley and Fenny Stratford).