Click through to see how the two worlds have collided to create some of fashion's most glamorous twinning moments.
Style icon Alexa Chung wore the exact same style as the duchess to the Nick Cave & The Bad Seeds x The Vampire's Wife x Matchesfashion.com party at Loulou's on Nov. 22, 2017 in London.
Photos: © Samir Hussein/WireImage and David M. Benett/Dave Benett/Getty Images for Matchesfashion.com & Nick Cave
The style from Warm & Wonderful was reissued in 2020 thanks to a collaboration with American brand Rowing Blazers.
Naturally, Queer Eye fashion expert Tan France was one of the first people to be pictured in the iconic design.
Photos: © Tim Graham Photo Library via Getty Images and Instagram/tanfrance
Elisabeth Moss donned a near-identical style from the British brand to the 33rd Annual Television Critics Association Awards on Aug. 5, 2017. Hers was the same dress Duchess Kate eventually wore!
Photos: © Ricky Vigil M/GC Images and Frederick M. Brown/Getty Images
Photos: © Getty Images
Photos: © Getty Images
Photos: Realis/SBM via Getty Images, James Devaney/GC Images
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Photos: Mike Coppola/Getty Images for Entertainment Weekly, Vittorio Zunino Celotto/Getty Images for Gucci, Taylor Hill/Getty Images
A month earlier, Pixie, 26, was pictured wearing a shorter version of the design at Temperley's London Fashion Week show.
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Photo: Getty Images
Kate and Paris Hilton
The Duchess of Cambridge stepped out in style on Nov. 3 wearing a dress from label Self-Portrait, a brand she's never worn before. And it looks like just one week prior to the royal's dazzling appearance, another famous face slipped on the $534 (£320) number: Paris Hilton. The socialite had stepped out in the same design at the amfAR gala in Los Angeles.
Photo: © Getty ImagesKate and Melanie Griffith
Weeks after the Duchess wowed in an off-the-shoulder midi dress by Barbara Casasola for the Art Fund Museum of the Year Award held at the Natural History Museum, Melanie donned the same dress in another shade across the pond for a Hallmark Channel TCA event. While Kate wore her glossy locks down with the frock, the Hollywood actress opted for an elegant updo.
Photo: © Getty ImagesKate and Drew Barrymore
For Kate's private engagement with the Bhutanese royals she wore a USD$1,495 Tory Burch floral mesh gown featuring retro-inspired flowers and side slits. Then, just hours after Kate stunned in the gown, actress Drew Barrymore attended the ASPCA Bergh Ball in New York City wearing the same style. Designer Tory acknowledged the coincidence was funny, telling Hello!, “I had no idea!”
Photo: © Getty ImagesPrincess Charlene of Monaco and Jennifer Lawrence
The Dior darlings rocked some of the couture house's finest dotted garments, with the Monaco royal dazzling in a cap-sleeved creation from the brand's fall 2015 collection while Jennifer showed off her toned arms in a sleeveless variation at the premiere of The Hunger Games: Mockingjay - Part 2 in London.
Photo: © Getty ImagesPrincess Charlene of Monaco and Tina Fey
The purple Atelier Versace gown that Tina wore to the 2016 Oscars is reminiscent of the striking indigo Ralph Lauren gown Charlene wore to a special dinner honouring the American label in 2013.
Photo: © Getty ImagesQueen Letizia of Spain and Cate Blanchett
Check out these belles of the ball! Here, both style icons shine in nude coloured gowns with floral embellishments - the monarch at a gala dinner with Japanese royalty and the actress to pick up an Oscar for Blue Jasmine in 2014.
Photo: © Getty ImagesThe Duchess of Cambridge and Sienna Miller
A little print goes a long way for this stylish duo, though Sienna is much more prone to rocking loud prints than Kate. A few days after the latter made a colourful entrance at the 100 Women in Hedge Funds gala in eye-catching Erdem, actress Sienna embraced the same colour scheme in a printed Marc Jacobs gown at the London premiere of her film Burnt.
Photo: © Getty ImagesLady Gaga and Princess Diana
Gaga channeled the late princess's iconic Victor Edelstein gown, made famous during her dance with actor John Travolta in 1985, at the 2015 Golden Globes. Unlike Diana and her pearl choker, the singer opted to let her custom Versace gown shine by leaving her neck bare.
Photo: © Getty ImagesCrown Princess Victoria of Sweden and Gwyneth Paltrow
The Hollywood actress had fashion fans green with envy as she walked the red carpet at the 2011 Bambi awards in a slinky, plunging number by Elie Saab. The following year at the 2012 Nobel Prize ceremony, Sweden's future queen shimmered in a similar emerald gown, which she paired with a show-stopping tiara.
Photo: © Getty ImagesChrissy Teigen and Princess Sofia of Sweden
It's no coincidence that the Swedish royal's powder-blue gown looks eerily similar to Chrissy's Oscars ensemble in 2015 - they were both created by master designer Zuhair Murad. The Sports Illustrated model opted for a sexier look complete with plunging neckline and high slit, while Sofia embraced a more modest silhouette to attend a pre-wedding dinner with her now-husband Prince Carl Philip.
Photo: © Getty ImagesPrincess Mary of Denmark and Sarah Paulson
Looking oh-so-elegant in off-the-shoulder midnight-blue gowns, these twins are both queens of the red carpet. Princess Mary steppe out at the 2014 Bambi Awards with her husband Crown Prince Frederik while Sarah Paulson attended the 2015 Emmys, where she was nominated for American Horror Story.
Photo: © Getty ImagesPrincess Eugenie and Madonna
The Queen's granddaughter and the Queen of Pop have both stepped out in this strappy Dolce & Gabbana black gown. Beatrice strutted her stuff in a charity fashion while Madonna kicked up her heels at Vanity Fair's 2007 post-Oscars bash.
Photo: © Getty ImagesThe Duchess of Cambridge and Angelina Jolie
Both Kate and Angelina have elegant dressing down to an art form, something they both achieved in light-blue chiffon gowns with cinched waists and keyhole detailing in the back. Kate slid hers on for the London premiere of Spectre, while the mother of six screened her most recent film By The Sea in New York.
Photo: © Getty ImagesPrincess Charlene of Monaco and Jennifer Lawrence
The Dior darlings rock some of the couture house's finest dotted garments, with the Monaco royal showing off a capped-sleeve creation from the brand's fall 2015 collection while Jennifer flaunts her toned arms in a sleeveless variation at the premiere of The Hunger Games: Mockingjay - Part 2 in London.
Photo: © Getty ImagesCrown Princess Victoria of Sweden and Sarah Silverman
Future monarch Victoria's ability to pull off a princess ball gown is in her DNA, but comedienne Sarah Silverman, here in bordeaux Zac Posen, proves that even Hollywood starlets can have royal-worthy moments.
Photo: © Getty ImagesCharlotte Casiraghi and Kate Beckinsale
These fashionistas know a good Grecian-inspired dress when they see one. The Monaco royal shined in pink Chanel at the 2010 Rose Ball, while Kate dazzled in draped Alice Temperley to celebrate Chopard's 150th anniversary in 2010.
Photo: © Getty ImagesQueen Rania of Jordan and Diane Kruger
It's hard to decide who wore this silver-and-white Elie Saab design better. Jordan's queen sported the number at the 2007 Bambi Awards, while fashion royalty Diane turned heads at the 64th annual Venice Film Festival.
Photo: © Getty ImagesPrincess Charlene of Monaco and Uma Thurman
With broad shoulders and long, lean physiques, these statuesque blonds definitely know how to work a halter neckline. While the Monegasque royal embraced a ruffled collar at the Princess Grace Awards Gala in 2013, the Hollywood actress opted for a sleeker finish at the 2014 Golden Globes.
Photo: © Getty ImagesQueen Letizia of Spain and Julia Roberts
Both Letizia and Julia put their own spin on classic black and white. And while the Spanish queen gave her ensemble a black-tie boost with a sparkling skirt, the actress proved that even a simple strapless dress and crisp white blouse can steal the show at a high-profile event.
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