The Royally Strict Fashion Rule Kate Middleton Rarely Breaks

The royal family isn't exactly known for their laid back approach to fashion. While former working royals like Meghan Markle, whose absolute best outfits so far have been in her 40s, sometimes skirted around restrictive styling protocols, there's one particular rule that Kate Middleton rarely ever breaks. For the royal family, it's generally frowned upon to wear black outside of a mourning period, and while Princess Diana (being the quietly rebellious spirit that she was) often broke this rule, Kate usually sticks to the status quo. Instead, she's generally seen wearing bright, pastel, and neutral hues, the encouraged color palette for public engagements. Kate Middleton's best wedding guest looks have certainly stuck to this pattern, and most of the time when we've seen her in black, it follows royal protocol.

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As you can see, that doesn't mean black isn't Kate's color — she looks totally regal in an all black ensemble. Fashion experts agree and even want to see Kate in more black. Former Vogue France editor Carine Roitfeld expressed as much in an interview with The Times in 2023. "She only wears black at the funeral," she said. "Maybe it's a law in the royal family, but I would dress her more in black. Black eyeliner. More Saint Laurent, more Chanel, more French."

Although Kate isn't much of a rule-breaker otherwise, there have been a few times the Princess of Wales has been caught wearing black outside of a mourning period. For starters, she wore a black lace Alice Temperley gown to the premiere of "War Horse" in 2012 (pictured above), a stunning number we're glad she deemed worthy of a little rule-bending. While it's not strictly all black (and probably the reason she thought she could get away with it), the sheer lace overlay is elegant and has enough brightness to avoid the mourning aesthetic. 

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Previously, though, Kate took a little inspiration from Diana, who famously loved wearing little black dresses. It's no secret that Princess Diana's revenge dress became one of the most iconic looks in fashion history, and in 2011, Kate channeled that energy. She wore a black strapless Alexander McQueen dress to the Sun Military Awards in London, and it certainly turned heads. Much like Diana's black off-the-shoulder revenge dress, this look was a velvet, form-fitting masterpiece. It complemented Kate so well, and she kept the look simple otherwise with just a few pieces of jewelry and a light curl to the hair.