Paper Monitor: A secret history

Enigma machine

A modest heroine.

Mavis Batey was a student in London when World War II broke out. She volunteered to work as a nurse, but was informed her fluency in the German language was more valuable to the nation.

"So I thought, great," she recalled, according to her Daily Telegraph obituary. "This is going to be an interesting job, Mata Hari, seducing Prussian officers.

"But I don't think either my legs or my German were good enough because they sent me to the Government Code & Cipher School."

In fact, her work as a codebreaker at Bletchley Park turned out to be far more sensational than she could have imagined.

In 1941, aged 19, she cracked a series of messages which revealed that Italy was planning to attack a Royal Navy convoy. British warships were able to catch the enemy by surprise by launching a pre-emptive attack, sinking three Italian heavy cruisers and two destroyers.

Later Batey broke a German Enigma machine, which led to the confirmation that the Nazis had fallen for the false "double cross" intelligence fed by the British. The upshot was that Hitler diverted two entire divisions on D-Day away from Normandy because he believed the invasion would take place in Pas de Calais instead.

Batey married a fellow codebreaker and after the war became a vigorous campaigner for the preservation of historic gardens. She died on Armistice Day 2013. Her obituary serves as a fine tribute.

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