Bletchley Park


Bletchley Park was purchased by the British Government in 1938 to be used as an intelligence and codebreaking centre in the event of war. Set in a secluded rural estate, but within easy reach of London, Oxford and Cambridge by train, this country house provided a safe but accessible wartime headquarters for intelligence operations. As the threat of war grew, Oxbridge academics were quietly recruited for unspecified 'war work' - the first codebreakers to visit Bletchley Park arrived disguised as 'Captain Ridley's shooting party'! Communication links were set up, timber huts were built to provide additional working space, and in August 1939 the Government Code and Cypher School (forerunner of GCHQ) moved from London. More people were gradually recruited to process the data flooding in from across the world, with up to 9,000 staff working at Bletchley Park, 75% of whom were women. The work was housed in an ever-expanding series of Nissan huts, each with its own specialist department working on one area of intelligence. Personnel were forbidden to discuss their work outside their own department in order to maintain the closest possible secrecy. Although relatively safe physically, many Bletchley Park personnel suffered mental health problems because of the continual stress of their work.

Bletchley Park's first major success was to break the Enigma code system used by the German armed forces. This was first achieved in January 1940, thanks to earlier work by Polish mathematicians and the brilliance of British codebreakers including Dilly Knox and Alan Turing. The Enigma codes were reset every midnight by the Germans, so a daily task by Bletchley Park codebreakers was to work out the daily settings, aided by the famous Bombe machine invented by Alan Turing and Gordon Welchman. Other codebreakers and analysts worked constantly on Japanese, Italian and German intelligence Lorenz ciphers.

Enemy wireless messages were picked up at wireless listening posts (Y Stations) across Britain and overseas; thousands of volunteer wireless operators recorded these intercepted messages onto paper and these were then sent by motorcycle or teleprinter to Bletchley park. Here, the messages were decoded, translated and analysed; all the details were indexed in a vast central card catalogue. Finally, the resulting top secret intelligence (known as 'Ultra') had to be disseminated to the relevant people. It was crucial that the enemy should not realise that their codes had been cracked, so information was often disguised to look as though it came from spies working behind enemy lines. Specialist Liaison Units were set up around the world to receive the Ultra reports via secure links and feed the information to commanders in the field.

Bletchley Park was crucial to the Allied victory. By deciphering the German, Italian and Japanese military codes and cyphers and analysing the information Bletchley park was able to warn the Allied forces of the enemy's intentions at sea, in the air and on land. It is thought that this intelligence shortened the war by up to two years and saved many thousands of lives. Despite the huge scale of this operation, the work of Bletchley Park remained a close secret and it is only in the last two decades that the names of these unsung heroes have become generally known, including the eleven Old Carthusians below.

Brigadier John H Tiltman CMG CBE MC (B1911)

John Tiltman's work was crucial to the success of Bletchley Park. He was a gifted mathematician who showed such early talent that he was offered a place at Cambridge aged only thirteen; his family could not afford to send him to Cambridge and instead he came to Charterhouse as a junior scholar. Tiltman saw distinguished service with the King's Own Scottish Borderers during the First World War and won the MC in May 1917. Between the wars he worked for the Government Code and Cypher School as a civilian Russian interpreter and cryptanalyst. In 1930 he was awarded an OBE in recognition of his outstanding work. During the 1930s Tiltman's team cracked the cipher for all Soviet radio communications with British communists, revealing secret Soviet funding for the British Communist Party and the names and activities of all those involved. Tiltman helped to recruit a number of university academics for intelligence work in 1938, and on the outbreak of war he was recalled to military service at Lieutenant-Colonel in charge of the military section of the GC&CS. Tiltman's extraordinary talent as a problem-solver and his linguistic ability enabled him to break the German railway enigma in February 1941, revealing German preparations to attack Greece and the USSR. Tiltman also taught himself Japanese in order to decipher the 'JN-25' Japanese naval code in 1939 and, later in the war, the Japanese military attaché code. Tiltman was Chief Cryptographer from 1941 onwards and became the Deputy Director (Military Wing) in 1944, universally known as 'The Brig'. Tiltman's many talents included the ability to manage a diverse and often downright eccentric workforce: in his own words, 'Cryptanalysts have to be handled delicately and do not take kindly to service methods of control, which are essential to the good working of signals'. He continued to work at GCHQ after the war. In 1946 he was awarded the US Legion of Merit in recognition of his close cooperation with the Americans and in 1954 he was awarded the CMG. He retired to the USA to be closer to his daughter and became a consultant to the National Security Agency; after his death in 1982 his name was added to the NSA Hall of Honour.

Frederick W Winterbotham CBE (R1915)

Fred Winterbotham had worked for MI6 before the war as an intelligence office, gathering information on Nazi military aviation; he successfully infiltrated the highest Nazi circles and paid regular visits to Germany. In August 1939 he established the intelligence reporting section at Bletchley Park (Hut 3). Once the Enigma Code was broken in 1940, he devised procedures for distributing this vital source of intelligence to the Prime Minister and to military headquarters and commanders in the field, whilst ensuring that the secret remained undetected. This information was simply referred to as 'Ultra', or (in RAF circles) as 'Fred' in honour of Winterbotham: he set up small Special Liaison Units (SLU) of carefully selected officers and technicians (mainly RAF cypher sergeants and Army Royal Signals radio operators) who were attached to each field headquarters that received Enigma. The SLU kept a very low profile and communicated the Ultra intelligence discreetly to each field commander. Winterbotham took an active role in training SLU operatives and educating receiving commanders of the need to maintain secrecy; Churchill sent him to the States to indoctrinate the Americans before revealing the existence of the Enigma decryption. The existence of Ultra remained a closely guarded secret until 1974 when Winterbotham finally broke his silence and published The Ultra Secret, telling the world of the extraordinary achievement of thousands of secret workers at Bletchley Park.

Lieutenant-Colonel F Peter Alexander (G1926)

Formerly a Captain in the Royal Artillery, Alexander worked in Hut 5 at Bletchley Park on Italian codes and cyphers; he organised 'cloak and dagger couriers' behind Germany lines in Italy. He left the military in 1947, but was recalled for the Korean War from 1950 to 1954 and then for a further four years in the War Department. He retired to Canada and became a timber farmer in Nova Scotia.

Harry Rupert Heap (R1934)

Harry Heap was always fascinated by radios and was one of the first people in Britain to obtain a transmitting licence in 1932. After studying at St Andrew's university, he worked for Ferranti and then Crompton Parkinson as an electrical engineer. Because of his expertise as a radio amateur he was recruited to civilian war service at Bletchley park in the Radio Security Service, working as a radio operator to intercept enemy transmissions.

Guy Malcolm Spooner MBE (W1925)

Malcolm Spooner was a distinguished zoologist with the Marine Biological Association, but also an able mathematician and so was recruited to signals intelligence. Initially he was based at Beaumanor Hall near Loughborough, a 'Y-station' for intercepting signals and identifying their source before passing the data for processing at Bletchley Park. Spooner is credited with solving the German army call sign system. He later worked in Hut 6 at Bletchley Park, on radio traffic analysis. After the war he returned to his work as a marine biologist; he is particularly well known for his work on insects and the flora and fauna of Devon.

Sir John Marriott (BH1945-1982)

Born in 1922 and educated at Merchant Taylors, John Marriott went up to St John's Cambridge in 1941 with a scholarship to read Mathematics, graduating two years later. He then served in the Army Operational Research Group and was sent to Bletchley Park in August 1944 where he worked in Block F with Maxwell Newman. This building (known as the 'Newmanry') housed operating equipment, including Colossus, for decrypting German teleprinters ciphers. After the war Marriott came to Charterhouse as a Mathematics beak; he was Housemaster of Girdlestoneites from 1960 to 1975. He was appointed Keeper of the Royal Philatelic Society in 1969 and was awarded the KCVO in 1995.

Michael Philip Ramsbotham (D1936)

Michael Ramsbotham won a place at King's College, Cambridge, in 1938, studying History under J H Plumb. In 1940 he joined the Royal Naval Volunteer Reserve as a sub-lieutenant (despite being unable to swim) and trained as a sonar detection officer (ASDIC). He was appointed to patrol duty in the Bristol Channel, but in 1941 was summoned to Admiralty Arch for a language test and then despatched to Bletchley Park, Hut 4. Here he joined a team of four people translating and analysing intelligence from Italian naval signals, mainly picking up details of enemy convoys carrying supplies to Libya. In 1943 he was promoted to assistant to Harry Hinsley (future author of the Official History of Intelligence in World War II). Work at Bletchley was very intense, with no allowance for holidays and a gruelling shift-work timetable; Ramsbotham suffered the additional stress of a secret homosexual affair with a colleague, Henry Reed, and in 1945 he suffered a breakdown and left Bletchley. After the war he worked as Secretary to Lord Mottistone and later as a probation officer; he was also a successful writer.

Lancelot Patrick Wilkinson (B1926, Charterhouse Governing Body 1954-70)

Patrick Wilkinson was a Fellow of King's College Cambridge from 1932, lecturing in classics. On the outbreak of war he was called to Bletchley Park as a civilian cryptanalyist, working in huts 4 and 5 on Italian naval intelligence. Here he met his wife, Sydney Eason, who also worked in the Naval section. In September 1943 he was deployed briefly to Algiers but then returned to Bletchley Park. He was Chairman of the Bletchley Park Recreation Club, an important social organisation for maintaining morale. The Club included drama, music and choral societies, it had its own library, and organised bridge, chess, Scottish dancing, and a variety of sports activities. After the war Wilkinson returned to academic life, becoming Vice Provost of King's College Cambridge in 1961.

Vincent Reiss (W1916)

Reiss served as a Staff Sergeant in the Artists' Rifles Regiment during the First World war and then joined the Reiss family business. During World War II he was the Transport Officer at Bletchley Park. This was a vast logistical role: motorcycle dispatch riders arrived at Bletchley Park throughout the day and night, delivering paper transcripts of encrypted radio messages from 'Y Stations' across Britain. In addition, a special bus service ran from Bletchley Park to collect personnel billeted in the surrounding countryside. Reiss master-minded all this travel, plus any other essential transport for Bletchley Park personnel.

Hugh Trevor-Roper (D1932), Baron Dacre of Glanton; Oxford Regius Professor of Modern History

In December 1939 Hugh Trevor-Roper was recruited from Merton College, Oxford, as an intelligence officer at the Radio Security Service, a branch of MI5, initially housed in Wormwood Scrubs and then at Arkley in Hertfordshire. Trevor-Roper's work entailed intercepting wireless traffic from the German military intelligence (Abwehr) and sending it on to Bletchley park. He was also a gifted analyst, often going beyond his remit in interpreting the data. A brilliant, but unconventional and free-thinking officer who was quick to criticise his superiors, Trevor-Roper was threatened with court martial on several occasions. The RSS was taken over by MI6 in 1941 and became part of MI6's counter-espionage section. Trevor-Roper became head of the intelligence section of the MI6 Radio Analysis Bureau and secretary of the joint MI5 and MI6 Wireless Committee. In 1944 Trevor-Roper joined the 'War Room', a counter-intelligence group planning the occupation of Germany. In the autumn of 1945 he was invited to compile an official report into the circumstances surrounding Hitler's death, which he later expanded into his acclaimed book The Last Days of Hitler.

Sir Marshall Warmington RN (G1928)

Marshall Warmington never visited Bletchley Park, but nevertheless played a significant part in its success.
In March 1941 Lieutenant Commander Marshall Warmington was serving on HMS Somali as Signal Officer of the 6th Destroyer Flotilla when she took part in the commando raid on the Norweigan Lofoten Islands. During the raid HMS Somali engaged and set fire to the German armed trawler 'Krebs'. Warmington and two other officers risked their lives to board 'Krebs' while she was still burning and searched her bridge. Her Enigma coding machine had already been thrown overboard, but in the captain's cabin Warmington found two Enigma rotor wheels and a quantity of secret documents, among them the Enigma Key Tables for the month of February 1941. The 'Kreb's Pinch' enabled Bletchley Park to make significant progress in breaking the German Navy's Enigma machine cyphers (codenamed 'Dolphin').


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