The fact that the Duchess of Cambridge knows how to dress is no secret. What remains hidden, however, are the secrets at the heart of some of her most iconic outfits. For the decade since her marriage to Prince William, Kate Middleton has assumed her royal duties with aplomb, never a foot awry of royal protocol, including the most important of all—to be neutral where necessary, both politically and personally, as a leader of the Commonwealth.  

But this particular royal tradition allows plenty of room for subtle sartorial messaging. It’s a loophole even The Queen has turned to for her most eyeballed public engagements. (Remember when Her Majesty wore a diamond and ruby tiara to a state banquet with former US President Donald Trump—a gemstone that symbolically guards its wearer against evil and disease? We’ll certainly never forget it.) 

The Duchess of Cambridge’s fashion ensembles have certainly been less pointed, but are just as powerful. Over the course of her royal career so far, many of her outfits have cemented themselves in the public consciousness, not just because of aesthetic, but their underlying significance. Her epoch-defining bridal gown by Alexander McQueen. Her red, peter pan-collared frock, worn whilst introducing the world to a newborn Prince Louis. Her high-necked floral Prada dress in the Kensington Palace gardens on the 20th anniversary of Princess Diana’s passing. 

What remains undeniable after an examination of Kate Middleton’s style is that few know how to exercise fashion with comparable finesse. From her choice of designer to the minute details of an accessory, Kate has used her clothing to chart her own progression in the public eye, transforming from fresh-faced ingénue to poised communicator, parent and future Queen of England.

Here, Vogue looks back at 18 of the Duchess’s most memorable outfits, and the meanings you didn’t know they carried.

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Kate Middleton’s Alexander McQueen wedding dress, April 2011

Whilst many will recall the hidden symbols on the Duchess of Sussex, Meghan Markle’s wedding veil—embroidered by former Givenchy director Clare Waight Keller with 53 floral and fauna representing the Commonwealth—you might not be aware that the Duchess of Cambridge did it first. On the sleeves of her now-iconic Alexander McQueen gown, the Duchess sported embroidered roses, thistles, daffodils and shamrocks, each a national emblem of England, Wales, Scotland and Northern Ireland. The method of embroidery was also conceptually significant, using a traditional, 17th century Irish technique called Carrickmacross. Kate's bridal gown was not worn simply to mark her union with Prince William, but also the United Kingdom as a whole.

Kate Middleton’s gold necklace, September 2020

On a visit to London’s Battersea Park, where she talked at length with parents about the impact of Covid-19 on their children, the Duchess of Cambridge wore a symbol of her own family. Eagle-eyed fans noticed that along with her white top and pink suit pants, Kate was wearing a brand new gold necklace with three circles, each featuring the first initials of her children’s names: ‘G’, ‘C’ and ‘L’ for Prince George, Princess Charlotte and Prince Louis.  

Kate Middleton’s polka dot dress, November 2022

The ongoing war between Russia and the Ukraine has drawn an outpouring of support from around the world. Back in 2022, when the invasion had only recently begun, the Duchess showed her support for Ukraine by opting for a polka-dot dress in Ukraine’s national colours. Worn to attend the Reading Ukrainian Community Centre, the yellow dots on the navy material were a more subtle nod. More recently, her support has been more easy-to-spot, wearing badges and sweaters directly referencing the country.

Kate Middleton’s coronation dress, May 2023

For King Charles III’s coronation, it was always going to be a red white and blue affair. The royal colours of the United Kingdom were the expected inspiration for the Duchess’s coronation outfit. Here, the Union Jack was everywhere to be seen in the form of a red Eponine coat, a white dress and a blue Self-Portrait gown, the white gown from Middleton’s go-to designer, Alexander McQueen.

Kate Middleton’s red houndstooth checked coat, February 2023

Sport has long been connected to the British Royals. The Duchess had recently been made the patron of the English Rugby Football Union, but with her title as Princess of Wales, when attending a rugby match between England and Wales, she needed to show her support for both teams. But the reference you may have missed in this look, is that the red and white houndstooth coat from Catherine Walker & Co, was a nod to Princess Diana, who wore a very similar look in the form of a Moschino skirt suit, back in the 1990 during Princess Eugenie’s christening.

Kate Middleton’s rented green dress, December 2022

At the 2022 Earthshot Prize in Boston, Kate Middleton wore a green Solace London dress rented from British fashion company Hurr. Wearing a rented dress, in such a vivid shade of green sends one of fashion’s strongest messages of sustainability/. The Earthshot Prize is an awards night established by Prince William and Sir David Attenborough which gives five grants each year to ideas, people, and projects that are combating global warming. While the green is far from subtle in the context of environmental messaging, the knowledge that the dress was borrowed, Instead of purchasing a brand-new gown, show’s the Duchess is proud to promote not only a more sustainable, but also affordable, way of dressing.

Kate Middleton’s yellow blazer, October 2023

While the Duchess has a veritable rainbow at her disposal in terms of outfit options, yellow is not a colour she turns to very often. However, for a visit to Birmingham in October 2023, yellow was the most important colour of the day. The visit was part of the Prince and Princess hosting a forum in the city for young people on World Mental Health Day. Yellow, is traditionally a colour that triggers happiness and has been used to commemorate mental health days around the world. An important message of solidarity to mental health by the Duchess.

Kate Middleton’s poppy-patterned Prada dress, August 2017

For a visit to Princess Diana’s memorial garden in Kensington Palace in August 2017, on the 20th anniversary of Princess Diana’s passing, the Duchess wore a bright green, tea-length dress by Prada, adorned with red poppies. While the flowers were a subtle tribute to her late mother-in-law, a traditional symbol of remembrance and respect for those who have died, the pussybow neckline was also a style favoured by Princess Diana during her lifetime. 

Kate Middleton’s green BAFTAs gown, February 2018

2018 was a revolutionary year for red carpets, with the emergence of the Time’s Up movement leading many celebrities to wear black in solidarity. Kate Middleton, however, appeared at the event in a forest green, off-shoulder gown by Jenny Packham. While some commentators concluded that the choice of colour was a consequence of the Royal Family’s historically bipartisan stance on politics, others believed that her dress was actually a subtle nod to the movement. The Suffragettes, in fact, wore green as one of their primary colours, believing it to represent hope. Kate's black belt was also seen as a show of support for the cause.

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Kate Middleton’s beige coat, January 2020

Around the time Meghan Markle and Prince Harry revealed they would be stepping down from their duties as senior royals, the Duchess of Sussex, The Queen and the Duchess of Cambridge all attended their public engagements in beige, within two weeks of each other. The choice was incredibly significant, especially for The Queen and Kate, who are usually seen wearing brighter colours. (The Queen herself has previously stated that she would “never wear beige”.) According to royal expert Elizabeth Holmes, it was a considered display of togetherness. "To have them in the same shade, I took very much to be a sign of unity,” Holmes said. “And then of course [The Queen] issued her statement of support to the Sussexes on January 13. Kate in brown on Monday morning was interesting, too, after she had been roped into the coverage.”

“Kate wore two pieces of brown: a khaki coat and a brown turtleneck—both of which were very visible in the shoulders-up shot of her driving the kids to school. It could be a coincidence but I think perhaps not!”

Kate Middleton’s red Jenny Packham dress, April 2018

Another dress designed by British talent Jenny Packham, the Duchess’s choice of vivid red when introducing a newborn Prince Louis was interpreted in two ways by avid onlookers. Significantly, Kate's dress, featuring a white peter pan collar, mirrored an outfit that Princess Diana had worn just after giving birth to her second son, Prince Harry, in 1983. Whilst Diana had worn a jacket and necktie, the similarity between the shade and the collar were undeniable. Other commentators also believed that the colours paid homage to Britain’s patron saint, St. George. On the saint’s holiday, which coincided with Prince Louis’s birthday, individuals often wear red and white to match the colours of St. George’s flag.

Kate Middleton’s pearl choker, April 2021

At Prince Philip’s funeral in April 2021, the Duchess of Cambridge offered a poignant tribute to the Duke of Edinburgh by way of a pearl choker. The necklace was first gifted to The Queen by the state of Japan in the 1970s. The accessory would become a favourite of Her Majesty’s, taken out of the royal jewellery collection and worn to events like former UK Prime Minister Margaret Thatcher’s birthday in 1995—importantly, it was also lent to Princess Diana, who wore the choker to a banquet at Hampton Court Palace in 1982. Kate's appearance in the same choker, therefore, was not only a sweet celebration of her grandmother and mother-in-law, but also of the late Prince, and the service to the country he had spent his life fulfilling.

Kate Middleton’s blue polka dot dress, July 2013

In July 2013, after giving birth to her first child, Prince George, the Duchess of Cambridge introduced him to the press on the steps of the Lindo Wing wearing a short-sleeved blue dress by Jenny Packham (who has, to date, designed all the dresses Kate has worn for the traditional photos outside St. Mary’s Hospital). The billowing, polka-dot frock was interpreted as a touching tribute to the teal, similarly dotted dress Princess Diana had worn while leaving the hospital with a newborn Prince William in 1982. 

Kate Middleton’s eagle-patterned dress, July 2017

While the Duchess of Cambridge is known for wearing designers from the countries she visits on her international engagements, sometimes her outfits’ hidden meanings have extended to the patterning of the fabric itself. During a trip to Germany in 2017, Kate sported a sleeveless dress by Markus Lupfer, a London-based, German-born designer, patterned with eagles in flight. In wearing the eagle, Germany’s national bird, Kate once again made a display of sartorial solidarity. Earlier in the visit, upon her arrival in the country, the Duchess had worn a Prussian blue coat dress, a reference to the invention of the colour in Berlin, as well as the cornflower, the national flora of Germany. 

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Kate Middleton's blue silk Beulah dress, July 2020

Nationwide lockdown during 2020 may have seen the Duchess of Cambridge refrain from her usual public engagements, but even over Zoom and during socially-distanced visits to hospitals and healthcare workers, she managed to make a serious sartorial impact. A particular outing to the Queen Elizabeth Hospital, in honour of the 72nd anniversary of the founding of Britain’s NHS, saw Kate wear a blue silk dress by London-based label Beulah. As many fans noted, the colour is the primary shade of the NHS. 

Even more impressively, the Duchess seemed to coordinate all of her looks during her virtual appearances in 2020, seen in reds, yellows, oranges and greens. It’s not a coincidence that rainbows were commonly used to symbolise solidarity with frontline workers during the pandemic.

Kate Middleton’s shamrock pin, March 2019

While many might see the Duchess’s shamrock pin from 2019’s St. Patrick’s Day as a mere, holiday-appropriate accessory, the brooch actually enjoys a rich history. According to Ella Kay, a jewellery reporter for the Court Jeweller, the shamrock pin “is loaned out to royal ladies who are associated with the regiment”, and has been worn by both The Queen and Princess Anne. Most critically, the shamrock—whose three leaves are said to represent faith, love, and hope—has traditionally been cited as a symbol of peace between Britain and Ireland. 

Kate Middleton’s lavender Emilia Wickstead dress, October 2018

After giving birth to Prince Louis in 2018, the Duchess of Cambridge returned to public service by attending the Global Ministerial Mental Health Summit in London, held a day before World Mental Health Day. Though her lavender Emilia Wickstead dress was relatively simple—worn with minimal jewellery and paired with a micro bag—the Duchess’ chosen hue was far more significant than it seemed. A colour often associated with healing, calm and relaxation, lavender was the perfect choice for an event dedicated to mental wellness.

Kate Middleton’s navy skirt suit, February 2020

The Duchess of Cambridge’s visit to the Defence Medical Rehabilitation Centre in Loughboroughworn in February 2020 saw her don a full-length navy skirt suit—a fashion decision that may only have derived meaning from coincidence, if it were not for the date. February 11 that year, however, marked the tenth anniversary of Alexander McQueen’s death, a designer who Kate famously wore down the aisle, and more than occasionally at public events. The dark-hued military jacket, skirt and bag were all from McQueen’s collection, a sombre, but moving ode to the designer’s legacy. 

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