The Poles had broken Enigma in 1932, when the encoding machine was undergoing trials with the German Army. But when the Poles broke Enigma, the cipher altered only once every few months, allowing time for code breakers to crack it. With the advent of war, security was improved and settings changed at least once a day, giving 158 million million million possible settings to choose from. With the threat of a German invasion, the Poles decided to inform the British in July 1939 about the Enigma machine.
Bletchley Park
The mansion at Bletchley Park was originally built in 1711. It was first known as Bletchley Park after its purchase by S. Seckham in 1877. Part of the 581 acre estate was sold in mid-1938 for use by the Government Code and Cipher School (GC&CS) and M16 in the event of a war.
Located 80 km North-West of London, the GC&CS took advantage of its geographical location. 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 West Coast railway line connecting London, Manchester, Liverpool and Edinburgh.
Personel
On the day Britain declared war on Germany, A. Denniston (operational head of the GC&CS) 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.
Denniston recognised, however, that the enemy's use of electromechanical cipher machines meant that formally trained mathematicians would be needed as well. Oxford's Peter Twinn joined GC&CS in February 1939; Cambridge's Alan Turing began working part-time in 1938 and reported to Bletchley the day after war was declared.
The first personnel of the 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 shortly after.
After the United States joined the war a number of American cryptographers were posted to Hut 3, and from early - 1943 onwards there was close co-operation between British and American intelligence. In contrast the Soviet Union was never officially told of Bletchley Park and its activities – a reflection of Churchill's distrust of the Soviets.
Intercepts and Code Breaking
The ‘Y’ Service, a chain of wireless intercept stations across Britain and in a number of countries overseas, listened in to the enemy's radio messages. Thousands of wireless operators, many of them civilians but also WAAF personnel and wrens (Women's Royal Naval Service), tracked the enemy radio nets up and down the dial, carefully logging every letter or figure. The messages were then sent back to Bletchley Park to be deciphered, translated and fitted together like a gigantic jigsaw puzzle to produce as complete a picture as possible of what the enemy was doing.
The process of breaking Enigma was aided considerably by a complex electro-mechanical device, designed by Alan Turing and Gordon Welchman called the Bombe. The Bombe ran through all the possible Enigma wheel configurations in order to reduce the possible number of settings in use to a manageable number for further hand testing. The Bombes were operated by Wrens working in Bletchley. The work they did in speeding up the codebreaking process was crucial.
Post War
Much of Bletchley's equipment and documents were destroyed at the end of the war,and the secrecy imposed on Bletchley staff remained in force, or were told a cover story about clerical or statistical work.Churchill referred to the Bletchley staff.
Bletchley Park
The mansion at Bletchley Park was originally built in 1711. It was first known as Bletchley Park after its purchase by S. Seckham in 1877. Part of the 581 acre estate was sold in mid-1938 for use by the Government Code and Cipher School (GC&CS) and M16 in the event of a war.
Located 80 km North-West of London, the GC&CS took advantage of its geographical location. 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 West Coast railway line connecting London, Manchester, Liverpool and Edinburgh.
Personel
On the day Britain declared war on Germany, A. Denniston (operational head of the GC&CS) 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.
Denniston recognised, however, that the enemy's use of electromechanical cipher machines meant that formally trained mathematicians would be needed as well. Oxford's Peter Twinn joined GC&CS in February 1939; Cambridge's Alan Turing began working part-time in 1938 and reported to Bletchley the day after war was declared.
The first personnel of the 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 shortly after.
After the United States joined the war a number of American cryptographers were posted to Hut 3, and from early - 1943 onwards there was close co-operation between British and American intelligence. In contrast the Soviet Union was never officially told of Bletchley Park and its activities – a reflection of Churchill's distrust of the Soviets.
Intercepts and Code Breaking
The ‘Y’ Service, a chain of wireless intercept stations across Britain and in a number of countries overseas, listened in to the enemy's radio messages. Thousands of wireless operators, many of them civilians but also WAAF personnel and wrens (Women's Royal Naval Service), tracked the enemy radio nets up and down the dial, carefully logging every letter or figure. The messages were then sent back to Bletchley Park to be deciphered, translated and fitted together like a gigantic jigsaw puzzle to produce as complete a picture as possible of what the enemy was doing.
The process of breaking Enigma was aided considerably by a complex electro-mechanical device, designed by Alan Turing and Gordon Welchman called the Bombe. The Bombe ran through all the possible Enigma wheel configurations in order to reduce the possible number of settings in use to a manageable number for further hand testing. The Bombes were operated by Wrens working in Bletchley. The work they did in speeding up the codebreaking process was crucial.
Post War
Much of Bletchley's equipment and documents were destroyed at the end of the war,and the secrecy imposed on Bletchley staff remained in force, or were told a cover story about clerical or statistical work.Churchill referred to the Bletchley staff.
"The geese that laid the golden eggs - but never cackled. - Winston Churchill's praise to the heroes at Bletchley Park."
The official historian of World War II British Intelligence has written that the intelligence produced at Bletchley shortened the war by two to four years, and that without it the outcome of the war would have been uncertain. The site is now an educational and historical museum memorialising and celebrating those accomplishments.
|
|
V
Congrats, we have finished the presentation. No for...... QUIZ TIME!
|
V
Congrats, we have finished the presentation. No for...... QUIZ TIME!