March 26, 2019 – Imagine sitting quietly in a college math class and receiving an invitation to a secret meeting. Once there, you are offered a job in Washington DC to identify patterns in letters that appear to be gibberish. The job sounds exciting and challenging. You’re in and then off to become a Code Girl, one of thousands of young women hired during WWII to decode Japanese and German communications.
The story of these women is told by Liza Mundy in her best selling 2018 book: Code Girls: The Untold Story of the American Women Code Breakers of World War II.
Girls who excelled in math and had a personality that matched the requirement to keep secrets were recruited at many colleges near Washington DC. Think of them as Rosie the Riveter holding a pencil instead of a riveting gun.
In her book, Mundy points out that in 1942, only 4 percent of American women had completed four years of college (p. 25). Recruiters asked college deans to recommend girls in math classes. They were creating the first ever units of female code breakers working for the U.S. military.
The story of these female math wizards who became code breakers has been somewhat lost to history because of the more well known British effort to decode messages at Bletchley Park in England. As told in The Imitation Game, a 2014 movie about Alan Turing and the effort to crack the German Enigma machine, Bletchley Park was the epicenter of the Allied decryption effort.
But a burgeoning decryption unit was forming in the United States although both the Army and Navy had their own units. British officials criticized America’s disjointed effort. Eventually, United States code breakers would shine, primarily decoding communications by the Japanese Navy but also helping the overall effort decoding German and Japanese messages.
Keeping the location of D-Day a surprise
The Allies launched a massive deception campaign in the months leading up to D-Day. That campaign included setting up a dummy base in England across the English Channel from Calais, France. Hitler believed the Allies would launch their invasion at Calais because of the short distance (about 30 miles) from Dover, England to Calais across the English Channel.
But Eisenhower decided on launching the invasion from Portsmouth, England, and many other ports along the coast, to land along the Normandy, France coast, which meant Allied ships would have to travel about 100 miles across the English Channel.
Hitler heavily fortified Calais and had issued orders to fortify Normandy as part of his “Atlantic Wall.” Heavy fortifications were built in Normandy but the Germans had yet to complete everything by D-Day.
Eisenhower used Gen. Patton as part of his deception campaign. Patton was well known as a fierce soldier in charge of the Third Army. Eisenhower made it appear Patton was establishing a headquarters near Dover, England, across from Calais, and assembling troops.
The deception campaign also included false communications purposely sent out by the Allies. The Code Girls in Washington DC were central to that effort. On page 305, Mundy describes the extent to which the code breakers had to ensure the fake traffic (communications) was plausible. If Patton was establishing a headquarters near Dover, communications would have to make sense.
The girls also intercepted incoming communications from Germany. They learned that Hitler believed the Allies would invade near Calais but he predicted Allies would conduct landings near Norway and Denmark to divert his attention away from Calais. He made the wrong assumption.
The location of Normandy as the invasion point had been kept a secret.
Ann White: Code Girl
Ann White was a code breaker recruited from Wellesley College. Ann knew the German language. She was chosen for a unit that worked on decoding messages intercepted from German Enigma machines.
Mundy describes the code breakers’ “rapt activity” on D-Day (pp. 304-309). Ann reported for her overnight shift at the Naval Annex at midnight on June 5, 1944. Just 90 minutes into her shift, identical messages were being intercepted from many German Enigma machines. The messages said: “Enemy landing at the mouth of the Seine.”
Over the next twelve hours, the girls decoded messages that provided vital intelligence for Allied commanders.
“The women learned that the French Resistance had acted swiftly to cut German communications. So much resistance, so many brave men working to defend the free world, had come together. ‘Even seated at our desks,’ Ann White would later write, ‘we felt the power of our country.’ The Normandy landings came as a complete surprise to the Germans – a surprise that saved an estimated 16,500 Allied lives.” (p. 308)
The experience would stay with Ann for the rest of her life.
“Ann would remember the Normandy invasion as one of the great moments of the war, and she would remember her wartime code-breaking service as the great moment of her life.” (p. 309)