Kate Middleton’s remarkable rise from middle-class university student to the Princess of Wales wasn’t accidental — according to multiple royal experts, it was carefully planned from the very beginning.

Royal author Simon Vigar wrote in “The Four Wives of Windsor” that Prince William’s “right-hand man” said Kate believed in “steady progress” as she learned the ropes of royal life, explaining, “We’re not going to rush our fences.”

“Catherine is no wallflower, somebody told me,” Vigar told Fox News Digital. “She’s got definite views about things. William obviously trusts her implicitly, and they need people like that. The queen needed Philip. Charles needs Camilla. And William needs Catherine. [And] she’s very clever. I reckon she’s probably the cleverest of a lot of them.”

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Vigar said that as a newcomer to the royal family, the Princess of Wales was determined to master the role, carefully carving out her place without overshadowing the monarch.

“For instance, they had various charitable interests, ranging from wounded service personnel to early years education and homelessness,” Vigar explained. “The person who linked all of those together under the mental wellbeing banner was Catherine. It wasn’t Harry or William. She was the one who said, ‘Do you know what the common denominator with all of this is? It’s mental wellbeing and mental health.'”

“And so, they started a new charity, sort of an umbrella over those,” said Vigar. “She will have learned from the other consorts. You’re always one step behind, but you’re there as a support. If you think something’s not quite right, you say it. Catherine’s the person that William can trust absolutely implicitly to give him impartial advice.”

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Kate’s journey to becoming the Princess of Wales was unlike that of the royal women who came before her.

“It’s a huge social leap that happened with Catherine,” said Vigar. “Lady Diana Spencer was a member of the aristocracy. Camilla’s pretty posh, as we say in this country, not quite as posh as Diana, but posh.”

“Catherine’s middle class,” he continued. “Her parents worked very hard. They built their own business. They were able to send their children to private school. … And it got her to St. Andrews University, where she met William, of course.”

The Prince and Princess of Wales married in 2011. Since then, Kate has devoted herself to several charitable causes and organizations focused on early childhood development, mental health, sports and the outdoors, among others.

“I think Kate was born for this role, as odd as that may sound,” Christopher Andersen, author of “Kate!,” told Fox News Digital. “She has a preternatural calm, a sense of self and confidence that borders on regal. I think she could have stepped into the role as queen-in-waiting back when she was still a student at St. Andrews University. As it turned out, it was William who dragged his feet and gave Kate 10 years to learn the ropes before popping the question.”

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“In many ways, I think there were some in the royal family who were intimidated by Kate’s innate grace and charm, not to mention her Diana-like appeal to the general public,” said Andersen. “She knew intuitively when to hold back, when to get along and when to stand her ground.”

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Kate’s patience wasn’t the only factor working in her favor. Royal experts told Fox News Digital that William’s lengthy courtship — once mocked by critics and tabloids — ultimately gave Kate something few royal brides have had: years to observe the monarchy from the outside before officially joining it.

Andersen argued that while critics once questioned why William waited so long to propose, the extended courtship gave Kate valuable time to understand both the institution and the intense public scrutiny that came with it.

“Knives were out from the moment Kate stepped into the spotlight a quarter-century ago,” he said. “She had walked a tightrope for years, no doubt about it. But the entire time she had the love and support of her husband. She seemed to understand instinctively that the cardinal rule was not to upstage the monarch.”

Royal broadcaster Ian Pelham Turner told Fox News Digital that, in his view, Kate wasn’t just finding her footing as a royal wife. She was preparing for the biggest job of her life.

“Kate has played the long game because she realizes she will one day be queen to a King William,” said Turner. “That training is far more extensive. There has been a steady build of PR power for Kate. It involves wearing the right clothes, manufacturing the right photographs to show a successful queen-in-waiting, as well as a devoted mother.”

Kate is expected to play a major role alongside William during this autumn’s busy royal calendar. The Sunday Times reported that she may join William in Mumbai, India, for the Earthshot Prize ceremony in November. Fox News Digital reached out to Kensington Palace for comment.

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If confirmed, it would mark Kate’s first Earthshot Prize appearance since the 2022 ceremony in Boston, the first held in the U.S. Kate didn’t attend the 2023 event in Singapore, staying home to support her eldest son, Prince George, during a week of school exams. She missed the 2024 awards in Cape Town and the 2025 ceremony in Rio de Janeiro as she scaled back public duties following her 2024 cancer diagnosis.

William launched the Earthshot Prize in 2020 to find and highlight solutions to some of the world’s biggest environmental challenges.

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“Kate and William are determined to shape their own destiny,” said Andersen. “They want to be avatars of change. They don’t want the monarchy to become so hidebound that it collapses from its own weight. At the same time, they respect tradition and history and aren’t about to throw the baby out with the bathwater. They are secure enough now to know they can rewrite the rules when it comes to publicity, pressure and palace expectations.”

“Kate is the monarchy’s most important asset,” he said. “True, she was given plenty of time to learn the ropes. But the truth of the matter is that Kate had it in her from the very beginning.”