Introduction
In the 1930s and early 1940s, women in the United States had limited career options. Most were expected to become teachers, wives, and mothers. Higher education rarely led to better job opportunities for women. However, World War II changed everything. The US military began recruiting educated women to serve in Washington, DC, opening up a world of possibilities that many had never imagined.
Thousands of American women answered the call to serve their country, often without knowing exactly what they were signing up for. These women became code breakers, playing a crucial role in the Allied victory during World War II. Their contributions were kept secret for decades due to a combination of national security concerns and societal sexism.
Liza Mundy's book "Code Girls" aims to shed light on these unsung heroines of World War II, telling their fascinating stories and giving them the recognition they deserve. This summary will explore the key ideas and events covered in the book, providing insight into the world of wartime cryptography and the remarkable women who helped shape history.
The Rise of Cryptography
Cryptography, the art of creating and deciphering secret codes, has been around for as long as humans have communicated. It became particularly important during times of war when keeping messages secret from the enemy was crucial. During the American Civil War, for example, the Confederates developed a cryptographic system so complex that even they had trouble using it effectively.
In the early 1920s, the United States lagged behind countries like France and England in code-breaking capabilities. Some American officials even considered it unethical to read other nations' secret communications. However, those who recognized the importance of cryptography often favored women for the job. They believed women were better suited to the intense focus and patience required for code breaking, although this assumption overlooked the fact that the work also demanded high intelligence.
Codes vs. Ciphers
To understand code breaking, it's important to distinguish between codes and ciphers:
Codes: Words, letters, or numbers that represent specific words or phrases. These can be used for brevity (like "OMG" today) or to disguise secret information. Codes require a codebook to decipher.
Ciphers: Either a scrambling of letters (transposition) or a substitution of individual units with unique units (like replacing 'r' with 't'). More complex ciphers were developed using mathematical equations and special machines as technology advanced.
Code breaking, or cryptanalysis, involved various tactics:
- Stealing enemy codebooks
- Studying the frequency and placement of specific words
- Using mathematical equations
- Making educated guesses based on context and known information
As radio and telegraph technology developed, governments needed more secure ways to communicate. This led to the creation of cipher machines and increasingly complex mathematical ciphers.
Pioneering Women in American Cryptography
Several women played crucial roles in establishing the foundations of American cryptography before World War II. Their stories highlight the challenges and opportunities faced by women in this field during the early 20th century.
Elizebeth Smith Friedman
In 1916, Elizebeth Smith arrived at Riverbank Laboratories in Illinois, initially hired to work on a far-fetched theory about Sir Francis Bacon being the true author of Shakespeare's works. However, her life took an unexpected turn when the eccentric millionaire who ran Riverbank, George Fabyan, transformed the facility into the government's first code-breaking bureau during World War I.
Elizebeth and her husband William Friedman, whom she met at Riverbank, suddenly found themselves leading the nation's primary code-breaking operation. After the war, they were hired by the army to work in Washington, DC. While William became the army's leading code maker and cryptanalyst, Elizebeth gained widespread media attention for her work leading a team that identified criminals during Prohibition. Her success set a precedent for female code breakers in the years to come.
Agnes Meyer Driscoll
Agnes Meyer Driscoll, a former math teacher from Illinois, became a key figure in the navy's small cryptanalytic office in Washington, DC during the 1920s and 1930s. She was the leading force in deciphering constantly changing Japanese codes and ciphers.
One of Driscoll's most impressive achievements was cracking a new Japanese fleet code introduced in June 1939. This complex system used two separate codebooks:
- A book that assigned numerical codes to words or symbols
- An "additive book" with numbers to be added to those from the first book
The resulting third set of numbers formed the final encrypted message. Driscoll figured out this system in less than a year, providing valuable intelligence about Japanese communications as the United States entered World War II. Unfortunately, the Japanese changed their additive books in early 1941, just before the attack on Pearl Harbor.
Recruiting Female Code Breakers
When Japan attacked Pearl Harbor on December 7, 1941, the United States was caught off guard. This surprise attack made it clear that the US military urgently needed to strengthen its intelligence capabilities. Even before the attack, both the army and navy had been actively recruiting code breakers, with a particular focus on women.
The Navy's Approach
The navy sought patriotic women with liberal arts educations and demonstrated talents in foreign languages, science, and math. Interestingly, they also preferred attractive women, assuming they would marry and leave the navy once the war was over.
In the fall of 1941, Wellesley College senior Ann White received a secret invitation to an interview. She was asked about her interest in crossword puzzles and her relationship status. After passing a code-breaking course, she was offered a civilian position with the navy in Washington, DC, with an annual salary of $1,800. The job came with strict secrecy requirements – she couldn't even mention the word "cryptanalysis" to anyone, including family members in the military.
The Army's Recruitment Efforts
As the U.S. Army Signal Corps' Signal Intelligence Service began its own recruitment drive, competition between the military branches intensified. The army focused on lesser-known southern colleges and even posted handsome officers in public places like hotels to recruit small-town schoolteachers.
In 1942, the United States made the controversial decision to admit women to its military. This move was embraced by thousands of women who rushed to enlist in the navy as WAVES (Women Accepted for Volunteer Emergency Service) and in the army as part of the Women's Army Corps (WAC).
Many of these women were trained in code breaking. By the end of the war, there were an estimated 11,000 female code breakers across the US military, representing more than 80 percent of the navy's domestic cryptanalyst personnel and 70 percent of the army's.
Life as a "G-Girl"
The women who moved to Washington, DC to become code breakers were known locally as "government girls" or "g-girls." While outsiders assumed they were doing menial office work, their actual duties were intense and crucial to the war effort. Despite the demanding nature of their jobs, life in the capital offered these women unprecedented freedom and experiences.
Living Arrangements
Many women working at Arlington Hall, the army's code-breaking venue in Virginia, lived in small rooms at Arlington Farms, a dormitory built to house 7,000 female workers. Others, like Virginia-born Dorothy "Dot" Baden and her friend Ruth Weston, rented apartments to escape the cramped dormitory conditions. The navy housed its female coders in barracks at Mount Vernon Seminary in northwest Washington, accommodating over 4,000 women.
Leisure Time and Travel
When not working long shifts, the g-girls used their free time to explore new places. They often took streetcars or buses to beaches in Virginia or Maryland. WAVES officers could travel anywhere by train at a discounted fare, and many code girls used their longer breaks to visit friends' families in distant states.
Social Life and Romance
Contrary to what one might expect, the war years were filled with frequent parties and social gatherings. Despite many young men being shipped off to fight, there was no shortage of romance with soldiers and sailors passing through the capital. Some women had married or become engaged hastily before the war, while others came to Washington to escape such pressures.
Regardless of their marital status, all the women wrote countless letters to men at war, often including portraits with notes scribbled on the back. This correspondence was crucial for maintaining morale. Dot Braden, for example, wrote to five soldiers simultaneously, including her two brothers.
Although Dot was engaged to one of these soldiers, George Rush, she ended up marrying another suitor named Jim Bruce after the war. Their marriage lasted 62 happy years until Jim's passing.
Breaking the Japanese Purple Machine
One of the most significant achievements in American code breaking during World War II was cracking the Japanese cipher machine known as Purple. This task fell to William Friedman's team of civilian code breakers in the army's Signal Intelligence Service.
Friedman passed on various techniques to his trainees, including the idea that any code could be broken if studied long enough. This was because even the most complex ciphering machines used rotors and wheels, meaning that cryptic patterns would eventually repeat.
The team studied romanized Japanese and analyzed commercially available machines that might have inspired the Purple design. They also used a technique called "cribbing," where certain known or guessed words served as starting points for deciphering the rest of a message.
As pressure mounted, the team hypothesized that Purple used a complex switching device instead of rotors for enciphering. To prove this, they needed to compare a Purple cipher to an already broken message from a less complex Japanese system.
Genevieve Grotjan's Breakthrough
On September 20, 1940, Genevieve Grotjan, a civilian army code breaker who had joined the team less than a year earlier, made a crucial discovery. Grotjan, an aspiring math professor who couldn't find a university job due to gender discrimination, approached the head of the operation, Frank Rowlett, with her worksheets.
Using her patience and sharp eye, Grotjan had identified where the pattern repeated – something her male colleagues had missed. This breakthrough enabled the Americans to recreate the Purple machine without ever seeing the original.
Grotjan's discovery was monumental, allowing the Allies to intercept and read Japanese communications encrypted with Purple throughout the entire war. This intelligence proved invaluable in shaping military strategy and ultimately contributed to the Allied victory.
Teamwork at Arlington Hall
While the navy maintained a more hierarchical structure, work at Arlington Hall was comparatively egalitarian. Even newcomers to the code-breaking world could become leaders of important units if they demonstrated skill and aptitude.
Ann Caracristi's Rise
One such newcomer was twenty-three-year-old Ann Caracristi, known as Annie to her coworkers. Despite having an English degree, Annie's supervisor, Wilma Berryman, recognized her talent for engineering and promoted her to lead a research unit.
Annie and Wilma were determined to crack the Japanese Army's code, which had resisted the efforts of many of their peers. They hypothesized that focusing on the addresses appended to the messages might provide a breakthrough. By using a crib from previously cracked naval messages, they hoped to make progress.
Their persistence paid off when Wilma Berryman discovered that the additive for part of the address was 7250. This breakthrough led to the monumental task of reconstructing the entire codebook, a process known as "book-breaking." Ann Caracristi proved to have an exceptional talent for this work.
Breaking the 2468 Code
In the early morning hours of April 7, 1943, Arlington Hall achieved another major breakthrough by cracking a Japanese water transport system code called 2468. This code provided extensive intelligence on Japanese shipping activities, including ship locations and destinations.
The success with the 2468 code led to a domino effect of more breakthroughs, including cracking the Japanese aviation code and a code that revealed the number of dead and wounded Japanese soldiers. By the war's end, Arlington Hall could read every message sent by the Japanese Army.
The Mail-Sorting Assembly Line
To handle the enormous volume of decoded Japanese Army messages, Arlington Hall recruited a fresh batch of workers to form a mail-sorting assembly line. This efficient system allowed for rapid processing and analysis of intercepted communications.
The intelligence gathered through this process had a significant impact on the war effort. In November 1943 alone, it helped the Allies sink 43 Japanese ships and damage 22 others. By cutting off food and supplies to Japanese soldiers, this work contributed substantially to the Allied victory in the Pacific theater.
Supporting the D-Day Invasion
The code girls' work extended beyond the Pacific theater and played a crucial role in supporting the D-Day invasion of Normandy.
Building the Bombe Machines
In 1943, a group of WAVES members was sent to Dayton, Ohio, to live on a campus called Sugar Camp. There, they helped build over 100 "bombe" machines, based on a design perfected by the British at Bletchley Park. These machines were created to decipher messages intercepted from the intricate German Enigma ciphering machine.
Gathering Intelligence
Intelligence gained from both the Enigma and Purple machines influenced the Allied Forces' planning of D-Day, particularly their decision to land in Normandy. The Purple machine, used by the Japanese foreign office, allowed Americans to read mail from Japanese diplomats in Europe. This revealed that certain parts of the coastline along occupied France were less fortified than others.
Additional intelligence came from German Army Enigma messages decoded by the naval bombe machines and a message decrypted in England detailing the defenses along the Normandy coast.
Operation Bodyguard
To ensure the success of the D-Day invasion, the Allies created a program of deception called Operation Bodyguard. This operation aimed to conceal the time and place of the invasion in occupied France. The Allies needed to convince Germany that they would invade in multiple locations, with the main attack occurring in the Pas de Calais region.
The g-girls played a crucial role in this deception. Using the code-writing skills they had developed while monitoring the security of America's own cryptographic systems, women in both the army and navy created coded messages about the location of the D-Day invasion using the American SIGABA machine.
The goal wasn't for the Germans to read the messages themselves, but to deduce from the radio traffic that the invasion would take place in Calais, with smaller landings in Norway and Denmark.
The Normandy Invasion
After months of meticulous planning, the Allies landed on the coast of Normandy on June 6, 1944, in the largest seaborne invasion in history. Although the invasion came at a great cost in American lives, the deceptive plan meant that German fortifications were substantially delayed. It was later estimated that the element of surprise saved approximately 16,500 Allied lives.
The Emotional Toll of Code Breaking
While the code girls took pride in their work, especially when it came to sinking Japanese ships, reading the details about the horrors of war took a psychological toll on many of them.
Facing the Realities of War
News about American casualties, particularly towards the end of the war, troubled many of the women. In some cases, they were aware that their enlisted husbands, boyfriends, or brothers were in danger without being able to do anything about it or share what they knew.
One poignant example is the story of Fran Steen, a Naval recruit who had risen to become a lieutenant. While on duty, her team intercepted a message indicating that a Japanese kamikaze raid would be targeting the navy destroyer her brother Egil captained. Although they notified the navy, nothing could be done to prevent the attack. Fortunately, Fran later learned that her brother was one of the few survivors.
Witnessing the End of the War
The code girls at Arlington Hall were among the first Americans to learn when the war was finally over. However, this knowledge came only after a period of intense waiting and uncertainty.
In 1945, Japan's refusal to surrender led to the unprecedented use of atomic bombs on Hiroshima (August 6) and Nagasaki (August 9). Even after these devastating attacks, there were still kamikaze attacks against American aircraft and warships in the following week.
On August 14, 1945, Arlington Hall translators received the message they had all been waiting for. Women like Virginia Aderholdt, who had spent four years in Japan and had been following Japanese communications for months, read intently as Japanese diplomats became increasingly discouraged by air raids on Japan and suggested ways to end the conflict.
When the code announcing Japan's intent to surrender was finally deciphered, the news spread across Arlington Hall like wildfire. However, the women had to wait until President Truman's official announcement that evening to share their joy with the outside world. After six long years, World War II had finally come to an end.
Post-War Challenges and Secrecy
In the months following the end of World War II, the women at Arlington Hall were thanked for their service and relieved of their positions. While army operations officer Stephen Chamberlin publicly announced that code breakers were responsible for saving thousands of American lives and shortening the war, he failed to mention that more than 10,000 of these cryptanalysts were women.
Classified Information
Much of the official information about the code girls' contributions to the war effort remained classified for over 70 years. The author, Liza Mundy, had to petition to have it declassified during her research for the book. This long-standing secrecy helps explain why the women's stories remained largely unknown for decades.
Mixed Career Opportunities
The code girls had varied experiences when it came to their post-war careers:
Continued work in cryptography: Some women remained at Arlington Hall and continued working as code breakers during the early years of the Cold War era. A select few, like Ann Caracristi, went on to work for the newly formed National Security Agency (NSA), which had merged army and navy code-breaking activities. Caracristi eventually became the first woman to serve as the NSA's deputy director.
Obstacles in other fields: Women who sought careers outside of government service often faced significant challenges. Due to the secretive nature of their wartime work, many WAVES recruits were denied the education opportunities promised to veterans in the GI Bill. For example, Elizabeth Bigelow was rejected from three architecture schools because they were reserving spots for veterans of the armed forces. Unable to disclose the true nature of her wartime contributions, she ultimately decided to marry and start a family instead.
Maintaining secrecy: The women held onto their secrets well into the 21st century. Virginia "Dot" Braden, for instance, had difficulty sharing certain words related to her work with her family, even after the NSA gave her permission to do so in her nineties. She had never spoken code-breaking terminology outside of Arlington Hall.
The Legacy of the Code Girls
By 2017, when Liza Mundy's book was published, only a handful of the code girls were still alive to tell their stories. This makes the documentation of their experiences and contributions all the more valuable, both as a way to honor their collective and individual achievements and to reveal an inspiring chapter in the history of American women.
The code girls' story highlights several important themes:
The changing role of women in society: World War II provided unprecedented opportunities for women to enter fields previously dominated by men. The success of the code girls demonstrated that women were capable of excelling in highly technical and intellectually demanding roles.
The power of diversity in problem-solving: The inclusion of women in code-breaking efforts brought fresh perspectives and approaches to the field, leading to significant breakthroughs that might not have been possible otherwise.
The importance of recognizing unsung heroes: For decades, the contributions of these women went unacknowledged due to secrecy and societal biases. Their story serves as a reminder to look beyond official narratives and seek out the hidden figures who shape history.
The lasting impact of wartime experiences: The skills and confidence gained by the code girls during their service influenced their lives and careers long after the war, even if they couldn't openly discuss their experiences.
The evolution of cryptography and national security: The work of the code girls laid the foundation for modern cryptography and signals intelligence, playing a crucial role in shaping the post-war intelligence community.
Conclusion
"Code Girls" by Liza Mundy sheds light on a fascinating and long-overlooked aspect of World War II history. The thousands of women who served as code breakers played a crucial role in the Allied victory, saving countless lives and significantly shortening the duration of the war.
These women, drawn from diverse backgrounds and educational experiences, proved their worth in a field previously dominated by men. They broke complex enemy codes, created deceptions that misled the Axis powers, and provided vital intelligence that shaped military strategy.
The story of the code girls is not just about their wartime achievements, but also about the societal shifts they helped initiate. Their success in these highly technical roles challenged prevailing notions about women's capabilities and opened doors for future generations of women in science, technology, and national security fields.
Despite the secrecy that shrouded their work for decades, the legacy of the code girls lives on. Their story serves as an inspiration and a reminder of the often-hidden contributions that shape history. By bringing their experiences to light, Mundy's book ensures that these remarkable women finally receive the recognition they deserve for their intelligence, dedication, and patriotism during one of the most critical periods in world history.