Patricia Bartley

Patricia Bartley was the Head of German Diplomatic Section at the tender young age of 24 for the Government Code & Cypher School (GC&CS) at Berkeley Street in London. Bartley left GC&CS permanently following a breakdown at the end of 1943. She would eventually return to her post and would go on to become one of the most significant cryptanalysts for the organisation during the Second World War.

She is best known for the work she did against the main German Diplomatic cipher system, known as FLORADORA (allegedly named after a British musical comedy), a double additive cipher, which had been a difficult problem to break for the GC&CS during the interwar period. As was the case with many cipher systems the German diplomats developed lax practices in using FLORADORA, which Bartley managed to exploit. Working closely with her team, which included the former Russian Tsar’s personal cryptanalyst, Ernst Fetterlein, the break into FLORADORA was achieved through traffic that was being intercepted between Berlin and the German Embassy in Dublin. By August 1942 Bartley’s team at Berkeley Street could read every single message. She would receive personal letters of commendation for the breakthrough from MI5 and the British Cabinet Secretary, Sir Edward Bridges.

A former student at Lady Margaret Hall at Oxford, she studied Philosophy, Politics and Economics (PPE). After the war she was tasked with writing two chapters of the Official History of the wartime GC&CS and would go on to a career with the Foreign Office.
She died on the 21st February 2021, aged 103.

^{Patricia Brown’s section at Bletchley Park, Buckinghamshire}