Marlene Dietrich is celebrated as one of Hollywood’s most glamorous movie stars, but the Berlin-born actress preferred being on the front lines with troops fighting during World War II.

“She was happiest serving the Allied troops during World War II,” the late icon’s grandson Peter Riva recently told Closer Weekly.

“She called them ‘my boys’ for the rest of her life, and they responded accordingly,” he added.

According to the outlet, Dietrich moved to the United States in 1930. In 1937, while filming in England, Dietrich was approached by agents of Adolf Hitler, attempting to convince the screen siren to return to Germany, the New York Times reported. Dietrich, appalled by the fascist regime, slammed the offer. Consequently, her films were banned in Germany. 

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Marlène Dietrich, entertaining on the front lines, signs autographs for American soldiers, circa 1945.

Marlène Dietrich, entertaining on the front lines, signs autographs for American soldiers, circa 1945. (Photo by Keystone-FranceGamma-Rapho via Getty Images)

The CIA shared that after Dietrich became an American citizen in 1939, she felt it was her duty to defend the country and use her talent to make a significant contribution to the war effort. With the beginning of U.S. involvement in the war in 1941, Dietrich became one of the first celebrities to raise war bonds.

She later roughed it out with other G.I.s sleeping in frosty dugouts near the front lines where she would sing and play a musical saw. Dietrich also recorded a number of anti-Nazi albums in German to create skepticism among listeners.

According to the Library of Congress, Dietrich made two overseas USO tours. The first was to North Africa and Italy, making her the first entertainer to reach rescued soldiers. For her second tour, which lasted 11 months, she entertained near the front lines in France and Germany.

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Marlene Dietrich meets a wounded soldier from Texas at a United States hospital in Belgium, November 1944.

Marlene Dietrich meets a wounded soldier from Texas at a United States hospital in Belgium, November 1944. (Photo by US Army/Interim Archives/Getty Images)

“It became a matter of passion and desire,” Riva explained about his grandmother’s determination to support the troops.

Danny Thomas used to say to me, ‘Your grandmother always wanted to get us killed,’” he continued. “‘If there was any daylight left, we went to entertain guys on the front line. Sometimes we did the whole performance just for 10 guys!’ She understood that if anything she could do to change the course of that war to defeat Hitler, it was worth doing.”

By 1945, Dietrich was awarded the Presidential Medal of Freedom.

“She was never more proud,” said Riva. “I think that is her great legacy.”

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Dietrich put on more than 500 performances for Allied troops throughout the war and many were on the front lines, the USO noted. However, Dietrich was willing to do so much more. She served meals at the Hollywood Canteen, which offered free food and entertainment to service members. Dietrich spent time in hospitals and visited wounded soldiers. She also teamed up with filmmaker Billy Wilder and created a fund to help Jews escape Germany.

During World War II Marlene Dietrich made more than 500 appearances before American troops overseas.

During World War II Marlene Dietrich made more than 500 appearances before American troops overseas. (Photo by Keystone/Getty Images)

When asked why she risked her life to support American soldiers, Dietrich responded, “out of decency.”

Back in 2018, Riva told Fox News Dietrich kept busy over the years as a beloved entertainer. He claimed that even at age 65, she was performing in 65 different cities in one year alone. 

He also dismissed rumors that Dietrich became a recluse in Paris as she grew older.

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“We used to struggle to pay her phone bill, which was $5,000 a month,” he said. “Hardly a recluse. And 20-30 letters a day? Good Lord, had the internet been around then, she would have been tweeting all the time!”

The gossip of Dietrich never leaving her bed may have come from the fact she only allowed family, close friends and her secretary to visit. And she didn’t want to be photographed.

Marlene Dietrich passed away in 1992 at age 90.

Marlene Dietrich passed away in 1992 at age 90. (Photo by Silver Screen Collection/Getty Images)

“She said, ‘I didn’t work for 60 years to have age destroy people’s image of me,’” Riva recalled. "'That’s what they need. That’s what lasts for hundreds of years.’”

Dietrich passed away in 1992 at age 90. Riva shared Dietrich’s final moments were far from tragic. 

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She died in May, her favorite month, said Riva. Her beloved flower, geraniums, were in full bloom. Her face, chosen for the Cannes Film Festival that year, filled the streets of Paris. And she was surrounded by photos of her admirers.

"She passed away looking beautiful," he said.