Kate Middleton's Fashion Failsafe—The Coat Dress

They've become a staple feature of Kate Middleton's working wardrobe since she became a member of the royal family in 2011. The modern longline, sleek and exquisitely tailored coat dress found its first royal fan in Princess Diana. Now as Kate Middleton has transformed her image into a bold, confident royal fashion figure she is bringing her coat dresses with her.

But what is a coat dress exactly and when did they make their way into the royal wardrobes? Newsweek has the answer.

Kate Middleton Coat Dress
Kate Middleton has adopted the failsafe style of elegant coat dresses for her working wardrobe. Photographed (L) in London February 7, 2016. (C) at Westminster Abbey December 8, 2021. And (R) at Westminster Abbey March 14, 2022. Karwai Tang/WireImage/Max Mumby/Indigo/Getty Images/Samir Hussein/WireImage

What Is a Coat Dress and Where Does it Come From?

The coat dress is a garment which blends the practical elements of its namesakes, eliminating the need to layer one on top of the other.

Variations of the coat dress have existed since the early twentieth century, though the style as we know it today was popularized in the 1980s and has become a formalwear staple ever since.

Diana's Royal Fashion Discovery

The coat dress was adopted by Princess Diana in the 1980s at the suggestion of her close friend and favorite fashion designer, Catherine Walker. The garment solved an issue that the princess faced in her working life which saw her constantly moving from outside to indoors on royal engagements.

One of Walker's most famous coat dress designs for Diana was commissioned for a state visit to the United Arab Emirates in March 1989. The resultant hot pink and red ensemble—paired with a matching Philip Somerville hat—caught the eye of the fashion press and signaled Diana's seamless transition from the sartorial extravagance of the 1980s into the streamlined chic aesthetic of the 1990s.

Walker's U.A.E. coat dress featured a clever trick to accentuate the princess's waist. The colors of the garment were separated by a line which was placed low down on the hips which the designer described as giving a "trompe l'oeil" effect.

Princess Diana Coat Dresses
Princess Diana owned multiple coat dresses designed by her friend Catherine Walker. Photographed (L) on a royal tour of Japan wearing Walker, November 14, 1990. And (R) Diana in Kuwait wearing Walker's tromp l'oile coat dress, March 14, 1989. Tim Graham Photo Library via Getty Images/Anwar Hussein/Getty Images

The benefit of the coat dress in royal dressing is that many different variations can be made in the same trusted style. Diana owned a number of coat dresses in different colors and with variations of embellishments but the overall silhouette stayed the same—except for the length of the skirt.

Writing in Catherine Walker: An Autobiography of the Private Couturier to Diana, Princess of Wales, the designer reflected on the varying lengths of Diana's coat dress skirts. She said:

"Over the years the princess's skirt lengths had been a busy topic for fashion journalists. It is true that they went up and down, and in my memory they are a little like a barometer that altered to reflect her changing life.

"At the time of her divorce they lengthened; shortly before her death they were probably the shortest. I always liked the fact that she didn't follow fashion but did what was right for her."

Kate Middleton and the Coat Dress Revival

During Diana's lifetime and after her tragic death in 1997, royal women did still wear coat dresses sporadically. But it wasn't until Kate Middleton joined the family in 2011 that the style had a real royal revival.

Staying true to the expert tailoring of Diana's 80s and 90s coat dresses, Kate went straight to the source for her working royal wardrobe by patronizing Catherine Walker & Co. The business maintains the sharp focus on structure and tailoring that it had under the leadership of Walker herself who died in 2013.

Today Walker's husband, Said Cyrus, heads the operation and he has created some of Kate's most iconic coat dress looks including the striking blue model worn to the 2022 Commonwealth Day service at Westminster Abbey.

Kate has also relied on other trusted designers to fashion her with coat dresses to include Christopher Kane who made an ice blue garment worn on three public occasions, and Alexander McQueen, the makers of Kate's wedding dress.

Kate Middleton Coat Dresses
Kate Middleton has many variations of coat dresses in her wardrobe from designers such as Catherine Walker and Christopher Kane. Photographed (R) at Westminster Abbey April 25, 2019. (C) on a visit to Bradford, January 15, 2020. And (R) at Buckingham Palace, May 17, 2016. Samir Hussein/Samir Hussein/WireImage/Max Mumby/Indigo/Getty Images/Victoria Jones/WPA Pool /Getty Images

When something works for Kate fashion-wise she has been known to stick to it, ordering multiples of her favorite shoes and even evening dresses in different colors. The same has been done with her favorite fashion failsafe, the coat dress.

To the funeral of Prince Philip in April 2021, Kate wore an elegant black Catherine Walker & Co. coat dress with a statement bow detail. The look was somber and dignified as the duchess did not pull focus from the important ceremonial events of the day.

In December later that year however, Kate did want to stand out while attending a charity Christmas carol concert she was hosting at Westminster Abbey. To this event, the duchess wore the same coat dress that she had done to Philip's funeral—only this time in a festive red hue. Kate's appearance that night was immortalized on film as she played the piano in a musical performance by the singer Tom Walker.

By incorporating the clean statement style of the coat dress into her working wardrobe, Kate has found a way to not only look smart at every opportunity but also to pay a subtle tribute to the garment's first royal champion, her mother-in-law, Princess Diana.

Kate Middleton Catherine Walker Coatdresses
Kate Middleton owns matching Catherine Walker & Co. coat dresses in red and black. Photographed (L) at the funeral for Prince Philip, April 17, 2021. And (R) at a Christmas carol concert at Westminster Abbey, December 8, 2021. Chris Jackson/WPA Pool/Getty Images/Max Mumby/Indigo/Getty Images
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