Prince Harry Claims Kate Middleton and Prince William Told Him to Wear Nazi Costume in 2005

Prince Harry claims that his brother Prince William and his sister-in-law Kate Middleton encouraged him to wear a Nazi uniform to a costume party in 2005.

The Duke of Sussex, 38, makes the allegation in his upcoming memoir Spare, which comes out Jan. 10, Page Six reported Wednesday.

According to the outlet, Prince Harry writes that the Prince and Princess of Wales, both 40, "howled with laughter" when they saw him in the outfit in 2005. Harry was 20 at the time, and the photo of him in a military shirt and red swastika armband holding a drink and a cigarette made headlines around the world.

According to Page Six, Harry claims in Spare that he debated between dressing as a Nazi or a pilot for the "Native and Colonial"-themed costume party. Prince William also attended, dressed as a lion.

"I phoned Willy and Kate, asked what they thought. Nazi uniform, they said," Harry writes, saying he brought the costume home and tried it on. "They both howled. Worse than Willy's leotard outfit! Way more ridiculous! Which, again, was the point."

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Prince Harry has previously expressed deep remorse over the offensive outfit, opening the incident in the Harry & Meghan docuseries, which premiered on Netflix in December 2022.

Describing the decision as "one of the biggest mistakes of my life," the Duke of Sussex said he "felt so ashamed afterward."

"All I wanted to do was make it right," he added. And while he "could've just ignored it and probably made the same mistakes over and over again," he learned from the experience.

"I sat down and spoke to the chief rabbi in London, which had a profound impact on me," he recalled on the TV series. "I went to Berlin and spoke to a Holocaust survivor."

The royal also addressed the idea of "unconscious bias" in his family, noting that while "it's actually no one's fault," that doesn't absolve one of responsibility.

"Once it's been pointed out or identified within yourself you then need to make it right," he said. "It's education, it's awareness and it's a constant work in progress for everyone ― including me."

Prince Harry was photographed wearing a Nazi soldier's uniform two weeks before the 60th anniversary of the liberation of the Auschwitz concentration camp.

After the incident, he apologized in a statement, saying, "I am very sorry if I caused any offense or embarrassment to anyone. It was a poor choice of costume, and I apologize."

The Board of Deputies of British Jews said at the time that it was "pleased that [Harry has] apologized for … his ill-judged actions."

"We would now want to concentrate on ensuring that everyone understands the evils and enormity of the Holocaust, and the resonance of the swastika, not only to the Jewish community, but to all in the United Kingdom affected by the Second World War against the Nazis," the group added.