Besides writing on Oxford, gardens, and Lewis Carroll's Alice, during WWII Mavis Batey was one of the top female code breakers working to crack the "Enigma" code for the Allies. She was born Mavis Lilian Lever in Dulwich, England, to a seamstress mother and postal worker father. She was brought up in Norbury and attended a convent school for girls in Croydon. She was 19 years old and studying German at University College, London at the outbreak of World War II when she decided
she had to "do something better for the war effort." She originally applied to become a nurse, but discovered that her linguistic skills were in high demand.
She was employed by the Government Code & Cypher School briefly at at first to check the personal columns of The Times of London for coded spy messages. Then she was selected to work as a code breaker at Bletchley Park. She served in a research unit reporting to Alfred Dillwyn "Dilly" Knox, chief cryptographer, who was working on the analysis of the Enigma ciphers. By March 1941, she had her first big success, breaking into the Italian Naval Enigma machine. She and her colleagues worked for three days and nights and discovered that the Italians were intending to assault a Royal Navy convoy transporting supplies from Cairo, Egypt to Greece. The information enabled Allied forces to destroy much of the Italian naval force off Cape Matapan, on the coast of Greece.
In December 1941, Mavis broke a message between Belgrade and Berlin that enabled the team to work out the wiring of the Abwehr Enigma machine previously thought to be unbreakable. This allowed the British to read German secret service messages and confirm that Germany believed the false intelligence they were being fed by British spies that the D-Day Allied invasion would take place on the Pas de Calais rather than in Normandy. While at Bletchley Park, Mavis met Keith Batey, a mathematician and fellow code breaker whom she married in 1942. After the war, she spent some time in the Diplomatic Service, and then raised her three children. She wrote a 2009 biography of her boss called Dilly: The Man Who Broke Enigmas. She also published a number of books on garden history such as Jane Austen and the English Landscape (1996) and Alexander Pope: Poetry and Landscape (1999). She served as President of the Garden History Society, of which she became Secretary in 1971. She was awarded the Veitch Memorial Medal in 1985, and was named a Member of the Order of the British Empire (MBE) in 1987.