Getty Princess Diana and Meghan Markle
Princess Diana loved the power and beauty of fashion and her daughter-in-law Meghan Markle is just as dedicated to style, fashion journalist Elizabeth Holmes tells PEOPLE.
They both used fashion to express their "individuality," which was especially evident as they exited royal life when they had some of their most iconic fashion moments.
"Diana was facing critics from inside the family and certainly from the public. And Meghan, her time was obviously much briefer as a female, working royal, but the amount of criticism and the racist coverage she received [was intense]," says Holmes, whose book HRH: So Many Thoughts on Royal Style published on Tuesday. "As you're getting married and getting to know a new family, and with Meghan and Diana having children, that was a lot to absorb."
She continues: "When they find their footing and when they know how to dress in a way that checks off all the royal boxes of expectations — but also displays their individuality and who they are — that's when I really smile. It's like they've hit their stride."
Getty The "Revenge Dress"
In HRH — which is a deeply reported look at the branding and fashion journeys of Queen Elizabeth, Princess Diana, Kate Middleton, the Duchess of Cambridge and Meghan Markle, the Duchess of Sussex — Holmes explores the ways in which Diana eagerly embraced trends and expressed her feelings through her style choices.
"What I came to really understand and appreciate was the ways in which she delighted in fashion, and introduced emotion into the equation," says Holmes. "She had these very distinct phases in her dressing and they track with the tumultuous personal life she was experiencing."
(Princess Diana and Princes Charles had a tension-filled marriage, which ended in divorce in 1996. A year later, the beloved princess died in a car crash.)
While Diana got a makeover with the help of British Vogue editors early on in her marriage, Meghan came into the royal fold with an established style, Holmes writes in HRH.
REX/Shutterstock Prince Harry and Meghan Markle on their wedding day
"Meghan came to the family several steps ahead of Diana and Kate. Meghan was an accomplished actress and knew the language of clothing... This is their whole job, to tell stories through clothes," says the author, who also notes Meghan's work with her lifestyle blog The Tig and her experience with red carpets. "So she hit the ground running."
During Kate Middleton's almost 10 years as a royal, she's helped the public reconnect with the monarchy through her accessible fashion choices. But, says Holmes, Meghan brought another level of excitement to royal fashion, just like her late mother-in-law.
"And then along comes Meghan. I don't want to mischaracterize [her style]. It wasn't out there by any means, but it was much more fashion-forward and much more modern," says Holmes, noting Meghan's decision to wear trousers at events. Meghan is also known to wear statement coats and sleek dresses and suits that are often in solid colors or modern prints. (She's been wearing four neutral colors, white, black, gray, and navy, for a decade, Holmes writes.)
"Within the royal fold, and within what we have come to expect from royal fashion, because of Kate and the ways in which she emulated the Queen," Holmes continues, "Meghan looked new and exciting, and modern, and sophisticated. She brought her Southern California relaxed vibe to a famously stuffy institution."
Meghan's decision to wear pants and menswear during public outings is a nod to Diana, who loved both styles and wore them often.
At the 2018 Endeavour Awards, Meghan's first evening engagement, she wore a black suit by Alexander McQueen instead of a gown. It sent a "strong message" to the public.
John Stillwell/PA Images/Getty Meghan Markle and Prince Harry at the 2018 Endeavour Fund Awards
The princess touring minefields
"[The suit sent] a very strong message that she was here to work," royal journalist Victoria Murphy said, according to HRH. "Just because she was a woman, it didn't mean she should be turning up in a dress and that's what we should be talking about."
Diana eagerly embraced the bold fashions of the '80s and '90s, while Meghan showcased her classic, "relaxed" California style during her time in the royal fold. But Holmes says their most striking fashion choices came as they were leaving the monarchy.
"It was sort of in the middle of her divorce, and afterward, you can tell [Diana] began dressing for what she wanted to wear. She knew what looked good on her body. She knew what photographed well," Holmes says. "There's a spread in the book about some Versace outfits. They're those bright, solid colors, very clean in spirit, and they fit like a glove. They're exciting but still modest and very much appropriate. She just looked fantastic."
Getty Princess Diana in Versace in 1996
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Meghan's all-star moment came during three engagements with Harry in the U.K. for their last appearance as official royals. (This past January, Meghan and her husband Prince Harry announced they were stepping down as working royals.)
"That trio of dresses on their farewell tour just showed how much [Meghan] understands fashion and how much we will miss from not having her as a senior working royal," says Holmes, who was impressed by the way the three dresses "built on one another."
She notes that Meghan's red cape dress "matched Harry's uniform exactly."
"It sounds like a small thing, but it's not," Holmes says. "You can see the same thing with her green dress for the Commonwealth service, which was her last dress that she wore. You could catch a hint of Harry's suit lining. There was just a brief gust of wind, and you saw that his suit was lined in green.
Dominic Lipinski/PA Images via Getty The couple at one of their last engagements as working royals
Samir Hussein/WireImage Meghan Markle and Prince Harry
"It's like they were projecting an image of unity in the smallest of ways," she continues. "But I think it's really powerful when you look at the resulting images."
Meghan, like Diana, is also devoted to advocacy and humanitarian work. At times, they've both played down their wardrobe in order to direct the focus to their causes (as Diana famously did during a walk through a minefield in Angola).
For Holmes, fashion is important because it's tied to the work of these royal women — and how they honor each other.
"All too often there's a rush to compare or, especially in the online space, [imagine] competition amongst various people," Holmes says of HRH. "I think each of these women is an individual, with individual goals within the monarchy, who use fashion in their own impressive way. I was really happy to weave in the ways in which I think they honor one another."