Usually, the upper floors of the office building at 263 Prinsengracht were silent. But on August 4, 1944, they came to terrible life. Miep Gies never forgot the sounds. “I could hear the sounds of our friends’ feet,” she wrote in her 1988 memoir. “I could tell from their footsteps that they were coming down like beaten dogs.”

Hours later, when she got up the courage, Gies went upstairs. She had helped her friends, the Frank family, live out of sight in the middle of Amsterdam for two years, bringing them the essentials of life as they hid from the persecution of Europe’s Jews. Now, the attic was trashed, ransacked by German police.

Then she saw it: a red checkered diary and years’ worth of papers strewn across the floor. Miep got on her hands and knees and gathered up the writing, then locked it in a drawer to wait for its author's return.

Anne Frank never came back. Within months of the arrest, the fifteen-year-old died of starvation and disease at the Bergen-Belsen concentration camp. But her diary outlived her.

Today, it is the Holocaust’s best-known and most widely read document, and its author is seen as a symbol of the 1 million Jewish children who were murdered during the Holocaust. The Diary of a Young Girl has sold more than 30 million copies, is required reading in many schools, and has been translated into more than 70 languages. The building where she hid draws over a million visitors each year. But how did the diary go from a pile of discarded papers to an international publishing phenomenon that still shapes modern historical memory?

Anne Frank received her diary as a gift on her thirteenth birthday in 1942. At first, it was her place to record observations about friends and school and her innermost thoughts. But when she and her family went into hiding the month after the diary began, it became a war document.

Inside the “secret annex,” as she called it, Anne documented her daily life, writing about herself, her family and the other people in hiding, Hermann and Auguste van Pels, their son Peter, and dentist Fritz Pfeffer. She wrote about their protectors’ efforts to smuggle in the essentials of life at great risk. And she increasingly thought about her work as a potential book.

In March 1944, Anne heard a radio broadcast from the Dutch minister for education, art and science, who was in exile in London along with other members of the Dutch government. “History cannot be written on the basis of official decisions and documents alone,” he said. “What we really need are ordinary documents—a diary, letters.” Anne wrote about the broadcast in her diary and decided to edit and rewrite it with an aim for publication.

By the time of her capture, Anne had rewritten much of her diary. Since both versions of the diary survive, so do Anne’s shrewd edits. She edited for content, length and clarity and made a list of suggested pseudonyms for the people in her life. “The differences between Anne’s initial efforts and her revisions vary from trivial to profound,” writes critic Francine Prose, “and deepen our respect for her as a writer.” Anne also wrote and rewrote essays and works of fiction. Her future as a writer was snuffed out when she was betrayed, deported and murdered.

Seven of the eight people in hiding died before the end of the war. The only survivor was Anne’s father, Otto Frank. When news finally came that Anne and her sister Margot had died, Gies gathered up the papers she had kept locked in the drawer since the Frank family’s arrest. “Here is your daughter Anne’s legacy to you,” she told Otto, placing the diary in front of him.

That legacy shocked Anne’s father. As he read Anne’s words, he realized that he had not really known his daughter. “The Anne that appeared before me was very different from the daughter I had lost,” he recalled. “I had had no idea of the depth of her thoughts and feelings.”

He began to translate the diary into German, sharing extracts with friends and family members. Otto made his own edits for content and clarity and excluded passages about conflict between Anne and her mother, Edith, and some sexual content. They encouraged him to publish.

But most publishers at the time were not interested in buying books about World War II—a war everyone wanted to leave behind. After a long struggle to find a home for the book, Frank eventually secured a publisher and the diary was released in 1947. The work was a combination of both of Anne’s diaries—the one she kept for private and the one she intended for publication. Its title, Het Achterhuis (The House Behind), had been chosen by Anne herself.

Despite worries that readers would not want to be reminded of the war, the book was enormously successful in Europe. Soon, it was flying off the shelves in the Netherlands and was joined by translations into French and German. But it faced an uphill battle in the United States. An advance copy of the French edition had been submitted to Doubleday, but rejected for an English translation deal. Then, editor Judith Jones discovered the book in a pile of rejects while her boss was at lunch.

“I read it all day,” she told the Jewish Chronicle in 2016. “When my boss returned, I told him, ‘We have to publish this book.’ He said, ‘What? That book by that kid?’” At the time, publishers thought that readers did not want to confront the Holocaust. But Jones felt that the book would find a strong market in the United States. The first American edition was published in 1952 with a foreword by former first lady Eleanor Roosevelt.

A gushing review from author Meyer Levin stoked national interest in the book. Days later, the book had gone into its second printing. The book was subsequently turned into a play by Frances Goodrich and Albert Hackett, who had written the screenplays of It’s a Wonderful Life, The Thin Man and other Hollywood classics. Their play was a smash hit, won a Pulitzer prize, and was adapted into a 1959 film that won three Academy Awards and was nominated for Best Picture. However, the play and film both downplayed the Franks’ Jewishness and focused on her brief romance with Peter van Pels.

Anne’s last words in the beloved play and film were her most famous quote, “In spite of everything, I still believe that people are really good at heart.” Those words, however, come before the end of the diary, and were written as part of a larger passage exploring the nature of good and evil and grappling with the horror she saw unfolding around her.

Anne Frank’s story quickly became part of school curricula around the world, with the diary becoming required reading in many school districts. For most readers, The Diary of a Young Girl is the only in-depth work they read on the Holocaust. But the work's fame is a double-edged sword: the diary does not show the aftermath of Anne's life in hiding—imprisonment, deportation, genocide—the horrors experienced by around six million Jews.

Anne’s story is also not representative: Only a small percentage of Jews went into hiding. The vast majority who did were betrayed, discovered and killed. Those who survived relied on non-Jews to support and protect them.

Although she was only 13 when she began documenting her wartime experiences, Anne Frank's diary was hardly the work of a naive writer. “I know I can write,” she wrote in April 1944. “but…it remains to be seen whether I really have talent.” An astute author and editor, Anne Frank’s carefully chosen words helped shape her legacy.

READ MORE: Who Betrayed Anne Frank?

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