Over a hundred years later, the garment—a mid-length frock with the fabric, buttons, and lapel of an overcoat—has become a power dressing staple. Stateside, the coat dress might be benched for summer, but that hasn't stopped royals across the pond from suiting up.
This week at the fun-to-say Order of the Garter service, Middleton wore a white Catherine Walker coat dress. Fitted at the top, the dress gave way to a flared, bouncy skirt. It also had black piping at the bodice and collar, drawing allusions to Eliza Doolittle in My Fair Lady.
Just a week before, Kate put on a banana yellow Alexander McQueen number. She paired the snug pencil dress with a swooping Philip Treacy fascinator. As the duchess stood to attention on the balcony of Buckingham Palace, she could not have appeared more British if she'd tried.
Call her Kate of 1,000 coat dresses: The duchess wore another Catherine Walker style for a military parade earlier this month. She also showed up to the Queen’s Royal Garden party in May decked out in a pale pink Alexander McQueen suit.
The decidedly militaristic style has charmed expat Americans, too. Just before the birth of her son in early May, Meghan Markle donned a black, cape-like Gucci coat for a ceremony honoring the victims of the Christchurch shooting. Days before, she put on an emerald Erdem version complete with glittering black embroidery.
Even Melania Trump wore two coat frocks during her week of Dynasty-era dressing in the United Kingdom. The pieces were probably her least egregious sartorial offenses in an insane wardrobe that included a UFO-inspired fascinator.
The first lady wore a trench dress by Celine while visiting 10 Downing Street. Melania cinched her bulky, massively oversized look with a thick black belt. Perhaps the style was coat dress-adjacent, as the sliver of a brown skirt peeked out from the bottom.
A few days later, Melania chose the style again for a D-Day anniversary ceremony in Normandy, France. This time her black, A-line coat dress came courtesy of Dior. She accessorized the somber look with four-inch heels and dark, round sunglasses.
This somewhat impractical garment—Is it a coat or a dress? What do you wear underneath?—may have roots in the 1900s, but it became tied to royal dressing near the latter half of the century.
British fashion writer Colin McDowell wrote in his book Diana Style that Prince Charles did not always approve of her royal uniform.
While visiting Japan in 1990, Diana wore a loud, red-and-green tartan coat dress by Catherine Walker. McDowell reported that when Diana asked her then-husband if he liked the dress, Charles replied, “‘You look like a British Caledonian air stewardess.’”
But nods to costume and regalia may just be why the coat dress has become a go-to for royalty. Julia Robson, a freelance fashion journalist based in London, told The Daily Beast that the style has become, “a very British look.”
“When you have that kind of dress, it’s quite tailored, so it’s safe to wear out,” Robson said. “The Duchess of Cambridge, Kate Middleton, might wear a lovely dress, but it could blow up and show her knees or a bit of thigh.” Not so with the fitted one-piece.
British summers are more temperate than sweaty, scorching, American ones, which makes the coat dress appropriate for all seasons. “It doesn’t ever get really hot here,” Robson said. “So the coat dress is perfect even if you don’t know what the weather is going to be like. You have your Spanx underneath and nothing else.”
The summer also holds a series of events known as “the Season,” where members of the elite gather to fête events like Royal Ascot, Trooping the Colour, and the Henley Regatta.
Fascinators are a dress code must for many of these gatherings. Opting for an all-in-one coat dress makes the tricky business of matching bonkers hats to the rest of an outfit a bit easier.
Robson added there is a bit of “sauciness” to a coat dress, especially ones that are double-breasted or mimic a tuxedo coat. “It looks like it’s meant to go with trousers, but you dispense those and just show off your legs and heels,” she said.
It makes sense that the young royals might want to inject some sex appeal into their wardrobes, which are often subject to staid protocol. Combine said “sauciness” with the fact that coat dresses have become synonymous with high society, and you've got the formula for a royally winning trend.