Code Girls The Hidden War and the Women Who Won It

Some stories of war are told through battles and weapons. Others are told through silence—through minds at work, hidden from the world. Code Girls is one of those stories.

Liza Mundy’s Code Girls uncovers a largely forgotten chapter of World War II: the thousands of American women recruited to break enemy codes. These women—many fresh out of college, some barely aware of what they were stepping into—entered a world of absolute secrecy. They weren’t allowed to speak of their work, not even to family. And for decades after the war, they kept that silence.

That alone makes this story remarkable.

What the book does especially well is reveal just how critical their work was. These women weren’t assistants or support staff—they were the backbone of American cryptanalysis efforts. They intercepted, translated, and broke complex Japanese and German codes, often working under intense pressure and in complete secrecy. Their contributions directly impacted naval battles, shaped strategic decisions, and in many cases helped alter the course of the war itself.

What makes this even more striking is just how many pivotal moments in World War II were influenced—directly or indirectly—by these women. Reading this, I found myself genuinely amazed. Some of the most historically significant outcomes of the war weren’t just decided on the battlefield—they were made possible by the work happening quietly behind the scenes.

An important detail the book highlights is that while many of these women served in uniform—enlisted in the U.S. Navy or Army—a large number did not. They were civilians, recruited for their intelligence, language skills, and analytical ability. Whether in uniform or not, they worked side by side, carrying the same burden of secrecy and the same responsibility. It challenges the traditional idea of what wartime service looks like.

But their story isn’t just one of contribution—it’s also one of contradiction.

These women carried immense responsibility. They handled information that could change the course of battles, and in some cases, the war itself. Yet at the same time, they operated in a world that often undervalued them. Many faced discrimination simply because they were women—paid less, given fewer formal acknowledgments, and often not taken as seriously despite the critical nature of their work. Even those in uniform navigated a system that did not fully recognize their capabilities or contributions.

And still—they delivered.

They performed under pressure, in silence, and without expectation of recognition. That dual burden—the weight of their mission and the reality of how they were perceived—makes their story even more powerful.

Another reason this book stands out is in how it tells that story. It never feels like it’s trying to push an agenda or force a message. Instead, it simply presents the facts, the people, and the impact. The author’s intent feels clear—not to convince, but to reveal. To bring forward a piece of history that had remained largely unseen, yet was absolutely essential to the outcome of the war.

There is also a quieter, more sobering layer to this story—what happened when the war ended.

For many of these women, the most important role they had ever held simply… ended. They stepped away from work that was intellectually demanding, meaningful, and vital to national security, and returned to a society that expected something very different from them. In many cases, they went from a life of independence, responsibility, and purpose back into more traditional roles as defined by the time. The shift was not always celebrated—it was often silent, just like their service had been.

It’s a difficult contrast to ignore. During the war, they were trusted with secrets that could shape the outcome of entire operations. After the war, many were expected to step back into lives where those capabilities were no longer recognized or needed in the same way. That transition adds a layer of sadness to an otherwise inspiring story—a reminder that their contributions were not fully acknowledged when it mattered most.

Mundy brings these women to life in a way that makes their contributions feel personal. You get a sense of where they came from, how they were recruited, and how they adapted to a world that demanded both brilliance and silence. Many were mathematicians, linguists, or simply sharp, capable individuals who had never been given opportunities like this before. The war opened a door—and they stepped through it.

For me, there really wasn’t a drawback to this book. I thoroughly enjoyed it from beginning to end. The depth, the detail, and the stories themselves only added to its impact. Instead of feeling overwhelming, it reinforced just how vast and important this hidden effort truly was.

In the end, Code Girls is not a story of traditional battlefield heroics. It’s a story of intellect, discipline, and quiet courage. It reminds us that war is not only fought with weapons—it is also fought with minds. And sometimes, the people who shape history the most are the ones working in silence, never expecting recognition.

This book brings them out of that silence—and gives them the place in history they have always deserved.