The Jewish Codebreaker Who Helped Alan Turing Crack the Nazis' Enigma Machine

Rolf Noskwith, the last of the brilliant mathematicians who worked under Alan Turing to decipher Nazi signals in WWII, died in January at 97. After the war he managed the family lingerie business.

Ofer Aderet
Ofer Aderet
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Ofer Aderet
Ofer Aderet

At the height of World War II, a group of Jewish mathematicians and linguists joined a secret unit of British code breakers operating out of Bletchley Park. One of them, Rolf Noskwith, had the honor of joining the team that entered the history books when it cracked the German naval fleet’s Enigma machine, thus deciphering the enemy’s signals and predicting its moves. He was the last surviving member of the team until his death in Britain on January 3, at 97.

Noskwith was born in 1919 to the Noskowitz family in the city of Chemnitz, Germany. His father Haim and mother Malka (nee Ginzburg), who owned a textile factory, migrated to Germany from Lodz in Poland due to the anti-Semitism they encountered from the Russian imperial authorities.

In 1932, with the strengthening of the Nazi party in Germany and following financial difficulties, they were again forced to migrate – this time with their children, Rolf and his sister Alexandra.

The destination was Britain, where their parents established a hosiery and lingerie factory in Derbyshire, in the East Midlands. His father, Haim, who in Germany was called Heinrich, now adopted the name Charles-Henry, and changed the family name from Noskowitz to Noskwith. They called the firm Charnos.

When World War II broke out in September 1939, Rolf Noskwith was a mathematics student at Trinity College, Cambridge. Like some of his classmates, he tried to get accepted to serve at the Government Code and Cypher School at Bletchley Park (105 kilometers – 65 miles – north of London) and join the Allied effort to decipher the Enigma code.

At first, though, his German roots caused his request to be turned down. Despite the fact that he escaped Germany as a Jew, the British were wary of German spies and saw him as a potential risk. In hindsight, perhaps there was another reason for the security fear the student Noskwith represented. In time, it became apparent that Trinity College was a breeding ground for some of the biggest traitors in British history: four of the five members of the “Cambridge Spies,” who acted in the service of the KGB during that period, studied there.

But in time, the British realized that Noskwith’s German background was an asset, as his command of the intricacies of the language could help in their work on deciphering the German code.

In 1941, when he was 22, Noskwith was accepted into the unit, having successfully passed an interview conducted by chess expert Hugh Alexander and physicist-author C.P. Snow.

Benedict Cumberbatch as Alan Turing in 'The Imitation Game.'Credit: AP

Noskwith worked in “Hut 8,” one of the shacks on the grounds of Bletchley Park where work on the German fleet’s codes was undertaken. He worked under the genius mathematician Alan Turing, considered one of the modern fathers of computing, who developed the “Turing Machine” (a simplified model of the actions of a computer) and the Turing Test (which checks whether a machine has artificial intelligence and its answers can be distinguished from a person’s).

Alongside them, he also worked with cryptanalyst and numismatist Joan Clarke, who was engaged to Turing.

Robert Hannigan, who headed Britain’s electronic intelligence agency GCHQ until resigning last month, recently published an article in the Jewish Chronicle commemorating Noskwith’s life.

In “The secret story of the Jewish codebreakers who helped win the war,” he wrote that the role played by Jews like Noskwith was “out of all proportion to the size of the Jewish community in Britain at the time.”

In this Thursday, Jan. 15, 2015 photo, an Enigma machine is displayed at Bletchley Park museum in the town of Bletchley in Buckinghamshire, England. Credit: AP

Indeed, the list of Jews who served at Bletchley Park is long and impressive: Walter Ettinghausen (Eytan), who would eventually establish Israel’s Foreign Ministry and serve as its first director general; his brother Ernest; the mathematician Max Newman, who developed one of the world’s first computers, Collosus; the mathematician Joseph Gillis, a founder of the Weizmann Institute of Science’s mathematics faculty; the mathematician Irving John “Jack” Good; the linguist Nakdimon Doniach; the mathematician Bernard Scott; Michael Cohen; and Morris Hoffman.

Their work produced results: The team in which Noskwith worked achieved the mathematical breakthrough that allowed the German fleet’s Enigma code to be cracked, and to listen to the enemy’s transmissions. Thus, as is written in history books, the team helped shorten the war by an estimated two to four years, saving many lives.

Noskwith enjoyed his work. In the book “The Codebreakers: The Inside Story of Bletchley Park,” he wrote that their work was so interesting that often staff members would refuse to go home, even though their shift had ended.

The German Enigma machine was based on a code that changed every letter in a cyphered message to another letter. The coding system decides which letter will represent another in the alphabet in the same code, which may be changed at any time. Every word in a transmission had an alternative code of its own. In effect, the number of possibilities was so high that deciphering the code was considered nearly impossible.

The intelligence services of several countries came on board, including France, Poland and Britain. The work began before World War II broke out. Among other things, a secret agent was recruited in the coding department of the German Defense Ministry, who passed on a partial operating guide for the Enigma; a code machine destined for Germany was also intercepted. A Polish mathematician, Marian Rejewski, managed to reveal that the Germans used one key for all their messages each day. He checked the coded transmissions and identified within them a systematic orderliness.

The Bletchley Park unit was established upon the breakout of war, and employed the best minds among mathematicians and linguists. They worked day and night to break the code. On January 17, 1940, the team deciphered a message transmitted between the Germans for the first time. A month later, the British fleet sunk a German submarine and found rolls of the Enigma code in the pocket of a dead sailor.

Sixteen months later, in May 1941, the British captured a German submarine with an Enigma machine, with the codes for that month. Ultimately, the British managed to attain total command of the German fleet’s Enigma code.

One of the transmissions Noskwith deciphered told of the disaster of the sinking of the Struma – a ship carrying illegal Jewish immigrants to pre-state Israel in February 1942. Only one of the 800 Jewish refugees on board, on their way from Romania, was saved.

In 1944, Noskwith deciphered transmissions connected to the invasion of Normandy and messages – which turned out to be false – about a successful assassination attempt on Hitler. In between, he stumbled upon reports of the Final Solution, which were particularly hard for him to read.

After the war, he married Annette Greenbaum, a German Jew who had come to Britain as a child on the Kindertransport. Her father, Franz Greenbaum, was Turing’s psychiatrist in the period leading up to his apparent suicide in 1954.

In the first years after the war, Noskwith continued to crack codes for Britain, this time at GCHQ, where he was involved with transmissions from Japan and Yugoslavia.

He later joined the family business at Charnos (an abbreviation of his father’s British name, Charles, and the surname Noskjwith) and ran the hosiery firm following his father’s death.

The story of the wartime code busters was commemorated in the book “Alan Turing: The Enigma” by Andrew Hodges, and the film “The Imitation Game,” which won an Academy Award in 2015 for best adapted screenplay (Benedict Cumberbatch played Turing, although Noskwith’s character wasn’t featured). Noskwith didn’t like the film and carried a list of all the mistakes he found in it in his pocket.

He is survived by his wife, Annette, son Adrian and two grandchildren.

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