The Biggest Revelations from Prince Harry's Book “Spare” 1 Year After Its Release

The Duke of Sussex doesn't hold back in his memoir, detailing his strained relationship with his brother Prince William and the death of his mother Princess Diana

Prince Harry didn't back in his memoir Spare.

The unprecedented book, which was released one year ago on Jan. 10, 2023, gives a candid look at the Duke of Sussex's life in the royal spotlight.

In addition to discussing his mother Princess Diana's death and how it affected him growing up, he also details his strained relationship with various members of the royal family, including his brother Prince William.

Published by Penguin Random House, the memoir was first announced in July 2021. In October 2022, Penguin Random House revealed the book's title would be Spare, a nod to the "heir and the spare" adage, pointing to different destinies that have separated Harry and his older brother William since birth.

Speaking with PEOPLE exclusively ahead of the book's release, Harry said his one hope with releasing Spare is to "turn my pain into purpose," adding, "If sharing my experience makes a positive difference in someone's life, well, I can't think of anything more rewarding than that!"

As for what he hopes his family's takeaway is from his memoir, he said: "I don't want to tell anyone what to think of it and that includes my family. This book and its truths are in many ways a continuation of my own mental health journey. It's a raw account of my life — the good, the bad and everything in between."

Read ahead for the biggest revelations from Prince Harry's book.

Related: Who Is Prince Harry's 'Spare' Ghostwriter? All About J.R. Moehringer

Prince Harry dubs his brother Prince William his 'archnemesis'

In a preview from Prince Harry's Good Morning America interview, host Michael Strahan inquired about his choice of wording for his brother Prince William, noting how he calls him his "beloved brother" and his "archnemesis" in the book.

"Strong words. What did you mean by that?" Strahan asked, to which Harry replied, "There has always been this competition between us, weirdly."

"I think it really plays into, or was played by, the 'heir/spare,' " he continued, referring to William's role as the future king while he has moved down the line of succession as Prince William and Princess Kate had children.

Related: Meghan Markle and Prince Harry's Netflix Docuseries: 22 Major Revelations

Prince Harry says that King Charles declared him a "spare" on the day he was born

According to a leaked extract reported by The Guardian, Harry claims that his father King Charles thanked Princess Diana for giving him a spare after his birth in September 1984.

"Early on, Harry recounts the story of how his father, now King Charles, supposedly said to his wife, Princess Diana, on the day of Harry's birth: 'Wonderful! Now you've given me an heir and a spare – my work is done,' " The Guardian reported.

The U.K. outlet adds that Harry's "resentment of being the 'spare' " is a "unifying theme" of the book.

Related: Prince Charles and Princess Diana's Relationship Timeline

Prince Harry drove through the tunnel where his mother Princess Diana died at the same speed

In PEOPLE's exclusive excerpt from Harry's memoir, he recounted the emotional moment he drove through the same Paris tunnel where his mother died in 1997, purposely asking the driver to drive at the same speed she was going when her and boyfriend Dodi Fayed's car crashed.

"It had been a very bad idea," he recalled in the book. "I'd had plenty of bad ideas in my twenty-three years, but this one was uniquely ill-conceived. I'd told myself that I wanted closure, but I didn't really. Deep down, I'd hoped to feel in that tunnel what I'd felt when JLP gave me the police files—disbelief. Doubt. Instead, that was the night all doubt fell away."

He continued, "I go the closure I was pretending to seek. I got it in spades. And now I'd never be able to get rid of it."

Prince Harry and Prince William asked Charles not to marry Camilla

Prince Harry recalled that he and his brother were initially resistant to the idea of their father marrying Camilla Parker-Bowles, following their parents' divorce and the death of their mother Diana in 1997.

Harry's initial fears that Camilla might be "cruel to me...like all the wicked stepmothers in the stories" were assuaged by private meetings with her, Harry wrote, but he and William still opposed Charles walking down the aisle with "the other woman."

The couple eventually tied the knot in 2005; Camilla received the title Duchess of Cornwall after their wedding and now is Queen following Queen Elizabeth's death in September.

Related: Prince Harry Wants Archie and Lilibet to 'Have Relationships' with Royal Family

Prince Harry claims Prince William and Kate Middleton encouraged him to wear his Nazi costume in 2005

In his memoir, Harry reflected on the controversial Nazi costume he wore in 2005, claiming that it was actually William and Kate who encouraged him to wear it.

Prince Harry said that the Prince and Princess of Wales "howled with laughter" when they saw him in the outfit in 2005. The outlet also reports that Harry claims he debated between dressing as a Nazi or a pilot for the "Native and Colonial"-themed costume party, and asked William and Kate for advice.

"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."

Prince Harry felt he lost his brother 'forever' after his wedding to Kate Middleton

Prince Harry recalled that Prince William's wedding to Kate felt like "yet another farewell."

"The brother I'd escorted into Westminster Abbey that morning was gone — forever," Prince Harry wrote. "Who could deny it? He'd never again be first and foremost Willy. We'd never again ride together across the Lesotho countryside with capes blowing behind us. We'd never again share a horsey-smelling cottage while learning to fly. Who shall separate us? Life, that's who."

Prince Harry added, "And I recall Willy walking her back up the aisle, and as they disappeared through the door, into the carriage that would convey them to Buckingham Palace, into the eternal partnership they'd pledged, I recall thinking: Goodbye."

Meghan Markle's comment about Kate Middleton's 'baby brain' caused a heated exchange between the duchesses

Prince Harry described a confrontation between Kate and Meghan after his wife referenced Kate's "baby brain because of her hormones" during a discussion ahead of Harry and Meghan's May 2018 wedding.

Kate, who gave birth to her third child Prince Louis one month before the Duke and Duchess of Sussex's nuptials, decided to raise the prior conversation with Meghan.

Meghan had previously discussed the dispute over bridesmaid dresses in her 2021 interview with Oprah Winfrey. After media outlets reported that Meghan made Kate cry in the lead-up to the royal wedding over Princess Charlotte's dress, Meghan gave her version of events. "The reverse happened," she said.

"And I don't say this to be disparaging to anyone, because it was a really hard week of the wedding, and she was upset about something. But she owned it, and she apologized and brought me flowers and a note apologizing," Meghan said.

Related: Prince Harry and Meghan Markle's Relationship Timeline

Prince Harry claims Prince William attacked him during a heated argument over Meghan Markle

In Spare, Harry detailed a specific argument with his brother in 2019 which reportedly turned physically violent.

Prince Harry claimed the argument started when Prince William called Meghan "difficult," "rude" and "abrasive," to which Harry replied that his brother was simply "parrot[ing of] the press narrative" about his wife.

Harry then accused his brother of acting like an heir, after which insults were exchanged. William reportedly claimed he was just trying to help.

"Are you serious?" Harry said in reply. "Help me? Sorry – is that what you call this? Helping me?"

Harry claimed that he tried to diffuse the situation by giving William a glass of water before the situation escalated.

"He set down the water, called me another name, then came at me. It all happened so fast. So very fast," Harry wrote in his book.

"He grabbed me by the collar, ripping my necklace, and he knocked me to the floor. I landed on the dog's bowl, which cracked under my back, the pieces cutting into me. I lay there for a moment, dazed, then got to my feet and told him to get out."

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