1. The von Trapps only had to cross the railroad tracks behind their villa—not the Alps—to escape the Nazis.

The Trapp Family Singers on tour in 1940. (Credit: Imagno/Getty Images)

In the climactic scene of “The Sound of Music,” the von Trapps flee Salzburg, Austria, under the cover of night and hike across the surrounding mountains to safety in Switzerland. Had they scaled the Alps in real life, however, the von Trapps would have crossed into Nazi Germany, not neutral Switzerland, which was approximately 200 miles away. “Don’t they know geography in Hollywood? Salzburg does not border on Switzerland!” complained Maria von Trapp after seeing the film. “In Hollywood you make your own geography,” came the reply from the film’s director, Robert Wise, according to author Tom Santopietro’s new book, “The Sound of Music Story.” The von Trapp’s real-life departure from Austria was less dramatic, if not just as timely as the one on the silver screen. In broad daylight, the family exited the gate at the rear of their villa and crossed the railroad tracks that ran behind it to board a train to Italy, where the family had citizenship once Captain Georg von Trapp’s birthplace became Italian territory in 1920. Salzburg residents saw off the captain, a pregnant Maria and the nine von Trapp children who were traveling with suitcases in tow under the guise of a family vacation in Italy. They left just in time; the next day the Austrian borders were sealed. During World War II, Nazi leader Heinrich Himmler used the von Trapp’s villa as a summer residence.

2. The names and ages of the real von Trapp children were changed for the film.

In actuality, the eldest von Trapp child was not 16-going-on-17-year-old Liesl, but Rupert, who was born in 1911 and a practicing physician by the time the family fled Austria in 1938. Liesl wasn’t even Liesl. In the film, all the names of the von Trapp children were changed.

3. Maria worked as a tutor to one von Trapp child, not a governess to them all.

In 1926, Georg von Trapp’s second-oldest daughter, Maria, contracted scarlet fever—the same disease that took the life of his first wife four years earlier—and could no longer walk the four miles to school. The retired naval captain paid a visit to Salzburg’s Nonnberg Abbey to find a suitable tutor for his daughter. Given Maria Augusta Kutschera’s training at Vienna’s State Teachers College for Progressive Education and her deteriorating health cloistered in the abbey, the 21-year-old was chosen for what was supposed to be a 10-month stint before she formally entered the convent.

4. The von Trapps married more than a decade before they fled Austria.

Unlike in the film when they wed as the Nazis were taking control of Austria in 1938, 47-year-old Georg von Trapp and 22-year-old Maria wed more than a decade earlier on November 26, 1927.

5. Three von Trapp children were omitted from the film.

Members of the von Trapp clan at a family-run hotel in Vermont in 1965. (Credit: Ted Russell/The LIFE Images Collection/Getty Images)

Due to the altered timeframe, none of the three children that the captain and Maria had together appeared in the movie version along with the seven children from the captain’s first wife. Daughter Rosmarie was born in 1928 and Eleonore arrived in 1931. The birth of son Johannes in Philadelphia in January 1939, months after the family left Europe, brought the number of von Trapp children to 10.

6. The captain was a warmer, more engaged father than he appeared on film.

One of the disappointments the von Trapp children had about “The Sound of Music” was the portrayal of their father as a detached disciplinarian. While he did use a whistle with a distinctive sound for each child and dressed them in sailor suits, the captain did not make his children march or stand at attention. “In reality, Georg was a warm and loving if somewhat overwhelmed father. It was actually Maria herself,” Santopietro writes, “with her emotionally stunted upbringing, who needed thawing.” Johannes von Trapp told the BBC that his father was “a very charming man, generous, open, and not the martinet he was made out to be both in the stage play and in the film. My mother did try to alter that portrayal for the film, but she was not successful.”

7. The sound of music filled the von Trapp house before Maria’s arrival.

Maria von Trapp’s declaration of intent to become a U.S. citizen. (Credit: National Archives)

The captain hardly disapproved of music. He and his first wife introduced music and song into their house and even taught their children how to play musical instruments including the accordion, violin and guitar. “My real mother was very musical,” daughter Maria Franziska von Trapp recalled in a 1999 interview with Vanity Fair. “She played violin and piano and we all sang before we met Maria. We had at least a hundred songs before she came. What she did was teach us madrigals, and of course this is very hard to do, but we found it was no problem for us.”

8. The driving force behind the Trapp Family Singers was left out of the film.

Like many families, the von Trapps went broke during the Great Depression, losing their fortune when their bank went under in the 1930s. Forced to raise money, the von Trapps took in boarders, including Father Franz Wasner, who recognized their musical talent after hearing them sing. As the family’s musical director, the priest crafted the von Trapps into professional singers. “He slowly but surely molded us into a real musical entity,” Maria von Trapp once said, according to Santopietro. After fleeing Austria with the von Trapps, Wasner toured with them through Europe and the United States. Santopietro calls Wasner “the driving musical force behind the Trapp Family Singers,” but he notes that the writers of the film believed that Wasner’s presence as a musical tutor would undercut Maria’s role, so the priest was replaced by the fictional music impresario Max Detweiler.