Did She Help Crack The Enigma Code?

Although Alan Turing was known for creating the machine that broke the Enigma code, he was actually one of a few people who worked together and one of those people was a woman.  A woman who I would never have heard of except for the movie.  Her name was Joan Clarke and she was even engaged to Alan for a while during the war.

Joan Clarke attended Cambridge to study maths and even got a double first when she finished in 1939 but she was unable to receive the degree until 1948 because Cambridge didn't grant degrees to women in mathematics.

It is at this point that history differs from the film.  In the film, they show her answering a puzzle in the newspaper which leads to her being the only woman asked to crack a tougher puzzle in under 6 minutes which she does and she is hired to work on the project. Turing did do this but she was not involved.

In reality, she was approached in 1939 while at Cambridge to attend the Government Code and Cypher School before being assigned to Bletchley as a clerk earning only 2 pounds a week.  This was much less than men doing the same job.  Note that the Government Code and Cypher School was created to break the German Enigma code. While doing this job, her ability shone through and she was transferred to Hut 8 which is where Turning and the others were working on cracking the Enigma code. In order for her to be granted a raise to go with this promotion, she had to be classified as a linguist since she was the first senior cryptanalyst.

In 1940, Turing wrote down his version of the Enigma theory for all the incoming recruits for huts 6 and 8 but before it was given to them, he had Clarke read it to see if it was understandable.  Due to materials captured in February and May of 1941, Hut 8 was able to make advances because they now knew some of the keys used for the starting position of the Navel Enigma machines.  In August 1941, the cryptanalysts in Hut 8 were able to begin using a code breaking technique referred to as Banburismus. 

Banburismus was developed by Turing and used a Bayesian sequential procedure designed to produce and handle a probability network containing thousands of pieces of evidence.  Clarke was one of the first females to learn this technique and was extremely good at it. This technique helped break the Naval Enigma code and by 1943, the machine (the bombe) built by Turing was used to break codes. 

Most of her time was spent decrypting Naval messages and forwarding them to Naval command to be used. Her good work was recognized and in 1944, she was made the deputy head of Hut 8. Unfortunately, she was still paid less than a man doing the same job and she would not rise any higher due to being female. After the war, she continued working for the Government Communications Headquarters (GCH) until she met and married a coworker in 1952. Due to his health issues, she left but 10 years later she returned to the GCH and worked there until she retired in 1977.  Once retired, she helped others when writing about Bletchley Park and World War II codes.

Although she and Turing became engaged in 1941 and he told her he was homosexual, the engagement did not last long because he felt the marriage would not last.  In addition, she did help create certain techniques but she never received credit for them because she was a women. We do not know all of her contributions due to the secrecy associated with Bletchley Park and thus do not know if she actually participated in breaking the Enigma code as much as shown in the movie.  We do know, she made some extremely important contributions but didn't receive the credit she could.  She was also considered one of the  foremost female cryptanalysits there and her contributions saved lives and helped Britain win the war.  

Let me know what you think, I'd love to hear.  Have a great weekend.