10 Photos That Perfectly Capture Princess Diana's '80s Style Evolution

1 | The engagement suit (1980)

Diana was incredibly unsophisticated about fashion in the early years and it was reflected in the clothes she chose to wear. Her wardrobe was unremarkable and demure, consisting of patterned sweaters and too long skirts. At the time of her engagement in 1980, she had just one evening gown. "Clothes are not my priority," she once said.

When she got engaged to Prince Charles, she didn't own a suit. Eager to appear conservative, she chose an off-the-rack suit by Cojana that she bought at Harrods with her mother's credit card. Anxious to be appear respectable, she asked that the skirt be made longer, which ultimately made her look even more matronly. The only positive about the look was its bright blue color that set off her eyes. Careful not to tower over her fiancé (Diana was 5'10"), she wore low-heeled pumps that became an overnight trend. Factories began churning out thousands of pairs of the Lady Di-inspired footwear.

After seeing the shots from the engagement photo call, Diana was determined to cultivate a more stylish appearance and vowed to lose weight. The suit was a catalyst for Diana, who then started her transformation from a Sloane Ranger into glamorous princess. And for the be-all-end-all of Diana looks, check out The Real Story Behind the Drama of Princess Diana's Iconic Wedding Dress.

2 | The infamous low-cut black dress (1981)

Shortly after the engagement, Diana chose a revealing black taffeta gown by Elizabeth and David Emmanuel, the designers of her wedding dress, for her first formal engagement with Charles, a gala at the Royal Opera House. She'd seen the dress hanging on a rack of samples on a visit to the designers' workroom. In an interview for my first book on the princess, Diana: The Secrets of Her Style, Elizabeth told me, "She tried it on and we thought she looked lovely in it—very different from how she had been seen before." At the time, it was the most sophisticated dress Diana had ever worn. But unlike most of her clothes, Diana never donned the gown again.

That's likely because the sight of Diana spilling out of the strapless, low-cut gown as she emerged from her car that night made the front pages of every newspaper in Britain the next day. Rather than admire the stunning princess that night, Charles was annoyed that Diana didn't know that royals only wore black when they were in mourning and also didn't appreciate so much of Diana's figure on display. Rather than guide her through the evening, he paid her little attention. It was Princess Grace, pictured here, who felt for Diana and affectionately told her, "Don't worry. It gets worse."

This occasion proved to be the first in a lifetime of events where Diana's undeniable star power and her ability to select the perfect dramatic dress would eclipse everyone and everything around her. The princess also devised a tactic that she continued to use for the rest of her life. When alighting from a car, she adopted the ladylike gesture of covering her décolletage with her clutch.

3 | The sparkly red evening gown (1981)

Determined to not make the same mistake by choosing a dress that was too revealing, Diana chose this pretty sequined red chiffon gown with a ruched bodice and ruffled hem from Bellville Sassoon, which she paired with silver accessories for the 1981 premiere of For Your Eyes Only in London. "She sparkled in it," said David Sassoon. The designer, known for his ultra-feminine dresses, quickly became her favorite. "She loved large, romantic kinds of dandy-like collars," Sassoon told me.

The designer would send Diana sketches for her approval and she'd return them with her notes on what she wanted to incorporate in the design. The styles that she was most enthusiastic about would be marked with "Please!" at the top of the illustration. Sassoon also created flowing, romantic maternity dresses for Diana. "She wanted something framing her neck that would distract from the fact she was big," he said.

The same thing Diana had done in popularizing frilly blouses and multi-strand pearl chokers she then did for feminine maternity designs. One of her favorite dresses while pregnant with Prince William was the empire-waist white silk gown she wore to meet Elizabeth Taylor in 1982. And for more celebrity encounters with Diana, check out Michael J. Fox Still Cringes Over Princess Diana Encounter: "It Was Agony."

4 | The polka dotted People cover girl (1981)

Having been inspired to dress in more age-appropriate suits, Diana discovered a way to look both pretty and respectable. She began gravitating toward better fitting styles in bright colors and made frilly pie-crust collared blouses her signature. When she visited Tetbury with Prince Charles for her first walk-about two months before her wedding, this polka dot suit by Jasper Conran charmed onlookers everywhere and landed her on the cover of People magazine.

5 | The lady in head-to-toe red (1981)

Diana was determined to refine her royal look and was beginning to perfect her style by wearing dramatic hats and silk dresses that were still modest but stylish. Diana dazzled in red—and she knew it. She also loved wearing red low-heeled pumps with white tights, which became something of a style staple for the princess.

A month before her own wedding, the princess stood out in the crowd in an all-red ensemble, wearing a Donald Campbell polka dress with a pie-crust collar when she accompanied the Queen Mother and Princess Margaret to the wedding of Nicholas Soames and Catherine Weatherall at St. Margaret's Church.

6 | The going-away white coat (1981)

Slung over her shoulders with a pretty printed crepe de chine Donald Campbell dress, Diana made an off-the-rack white coat look like the height of fashion as she and Charles set off on their honeymoon. She wore the designer's clothes until 1986. "I don't think I would have chosen many of my designs that she wore," Campbell told me. "She chose what she wanted. She bought everything off the rack, nothing was made for her."

7 | The one-shoulder evening gown in Australia (1985)

On an official visit down under, Diana tapped the Emmanuels to create another one of their frothy gowns for her. The drop waist, one-shoulder aquamarine gown in silk organza with crystal beading was a quintessential '80s look and one of her favorite dresses. With emerging confidence, Diana increasingly chose more fashionable looks and dressed like no other royal before her. She was expected to dress like a princess while abroad and this ballgown fit the bill as she swirled around the dance floor with Charles at the Southern Cross Hotel in Melbourne.

Royal tours always required intense organization. Every detail was meticulously cataloged so Diana always knew when and where she last wore an outfit. One dresser always came along on the trips to carefully maintain the princess' wardrobe, which, by the mid-'80s, consisted of more than 80 suits, 150 gowns, over 70 hats, and 100 of pairs of earrings.

Rarely, if ever, did anything slip through the cracks. But it did on this trip. When Diana realized she'd accidentally left behind her tiara on the Australia tour, she substituted her Queen Mary emerald and diamond choker and wore it as a headband.

But behind the scenes, a missing tiara was the least of Diana's problems in Australia, as the War of the Wales had begun. "Whatever was going on behind palace doors, Diana was determined," Elizabeth Emmanuel told me. "She always looked so happy when she wore something from us." And for more on the dark underbelly of this trip, check out 5 Heartbreaking Ways Princess Diana Defines "The Crown's" New Season.

8 | The "John Travolta" dress (1985)

Diana dazzled the star-studded crowd at the White House state dinner in 1985. She wore her multi-strand pearl and sapphire choker with one of her most famous and favorite gowns. The princess glided across the dance floor with none other than Mr. Saturday Night Fever himself, John Travolta, in a draped blue velvet gown by Victor Edelstein.

Edelstein told me the princess first saw a burgundy version of the dress in his studio and asked that it be made for her in midnight blue. The fittings for the gown took place in her private apartments at Kensington Palace. Afterwards, Diana was so thrilled with her gown that she rushed to show it to Prince Charles, who reportedly told her she looked beautiful and that it would be perfect to wear with her stunning statement necklace. And for more on a key piece of the princess' jewelry, check out the story behind Meghan Markle's Gold Cartier Watch That Once Belonged to Princess Diana.

9 | The designer that defined Diana's style (1989)

After a great deal of experimentation, by the late '80s, Diana had chosen Catherine Walker as her go-to designer for the many looks she would wear for the rest of her life. Walker, who often collaborated with milliner Philip Somerville, designed many of Diana's most memorable looks and is best known for her role in transforming the princess' ultra-feminine style into a chicer, more tailored aesthetic, as shown here. Catherine and Diana became great friends and when the princess tragically died in 1997, she was buried in a Catherine Walker black coat dress. And for more regular royals updates, sign up for our daily newsletter.

10 | The full-on Dynasty (1989)

Diana ended the decade looking drastically different from the shy teenage girl introduced to the world nine years earlier. She chose this show-stopping Philip Somerville hat for a visit to Abu Dhabi to complement her royal blue-and-white Catherine Walker suit and matching clutch. Although she wasn't a huge fan of hats, she is credited for bringing them back into fashion.

Somerville created the blue silk turban because Diana wanted to honor the country's custom, which calls for women to cover their heads. But in an interview for my book, Somerville, who made Diana's hats for virtually all of her official engagements, said there was also a practical reason behind her decision to wear the dramatic design. "She was very conscious of her hair and that it flattered her face." But Somerville thought something was missing. "I took two or three brims and put a little cuff on it because sometimes we'd juggle brims and crowns. I put the brim she chose over the turban and she thought it was marvelous," said Somerville. Joan Collins could not have worn it better. And for more inside secrets about the princess, check out 23 Facts About Princess Diana Only Her Closest Friends Knew.

Diane Clehane is a New York-based journalist and author of Imagining Diana and Diana: The Secrets of Her Style.