Marilyn Monroe once met the Queen at a film premiere in London -- see the rare regal footage!

FLASHBACK: Marilyn Monroe Meets the Queen of England in This Rare Footage
FLASHBACK: Marilyn Monroe Meets the Queen of England in This Rare Footage

Marilyn Monroe once waited in line to meet Queen Elizabeth II.

Rare footage of the late Hollywood star, who would have turned 90 on Wednesday, recently emerged, revealing a moment when she met the Queen in London's Leicester Square on Oct. 29, 1956. At the time, both regal ladies were just 30 years old.

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The meeting took place at the 1956 premiere of The Battle of the River Plate, a British war film. Monroe was there to accompany her then-husband, playwright Arthur Miller.

During the royal encounter, Monroe donned a strappy, silk dress with gloves as she shook the Queen's hand, curtseyed and smiled. Her Royal Highness looked equally as glamorous in an off-the-shoulder gown and sparkly Grand Duchess Vladimir tiara.

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The Queen took the throne when she was 25 years old, following the death of her father, King George VI. On April 21, she celebrated her 90th birthday, surrounded by her family and furry friends.

In honor of the milestone, famed photographer Annie Leibovitz snapped stunning photos of the monarch at Windsor Castle for Vanity Fair's Summer issue.

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"The most moving, important thing about this shoot is that these were all her ideas," Leibovitz told the glossy. "She wanted to be photographed with her grandchildren and great-grandchildren; her husband, Prince Philip, the Duke of Edinburgh; her daughter, Anne, the Princess Royal; and her corgis."

Watch the video below to hear more.

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