Princess Diana's hairstylist reveals the moment she decided to cut her hair off after a 'Vogue' shoot

Princess Diana is well known for her iconic short haircut, but fans never realized the story of how it came to be. Now, Sam McKnight - the man responsible for giving the late Princess of Wales’ hair the chop - has revealed details of the experience in a new book.

The Scottish-born stylist revealed that his royal client found the guts to allow him to give her her famous crop cut after posing for the front cover of Vogue.

Sam and Diana’s paths crossed in 1990 during a fashion photoshoot. “Mary Greenwell and I were told it was someone important, but we had no idea who,” he writes in his new book, Hair by Sam McKnight. “We guessed it might be Margaret Thatcher, and then in walked Diana.”

TAP TO VIEW GALLERYPrincess Diana's short hair became a trademark

Princes Harry and William’s mother was being photographed at the time by Patrick Demarchelier for British Vogue. The hairstylist reveals, “I faked a short style for the shoot, using hair grips to tuck her shoulder-length hair under the tiara,” which she ended up liking.

After the shoot, the royal asked Sam, “What would you do with my hair if I gave you free rein?’” to which he replied, “I would cut it all off.” Surprisingly the royal mom of two agreed and he cut her hair right then and there.

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The hair guru confesses, “I had no idea what was about to ensue. The style became front page news and there were journalists camped outside my parents’ house — they had to move out for two weeks.”

Diana met stylist Sam McKnight on a shoot

From then on, the pair formed a friendship and Sam began seeing the Princess every week when he was in London. He shares, “We’d often watch Channel 4 soap Brookside at the palace together while I was doing her hair and I went on a number of her official trips.”

Sam also helped facilitate a meeting between the royal and Vogue editors in Knightsbridge, where the group discussed a photo of Diana that would make a great magazine cover. He says, “In the end, this iconic image of her in a black turtleneck with short hair, resting her chin on her hands, was the cover in December 1991. She had just stopped biting her nails and was so proud of how they looked!"

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In his book, Sam admitted that he was responsible for Diana's slicked-back look. “I loved Diana looking more spontaneous,” he pens. “She even looked great coming out of the gym with freshly showered hair. During one particular portrait we worked on, Lord Snowdon had the inspired idea to photograph her with wet hair. I first tried slicking her hair back in a private shoot and she looked incredibly chic."

Sam continues, "Even though she was a bit nervous, she was still open to new ideas regarding her look. So for the Council of Fashion Designers Awards in New York, we decided she would try it out in public — the flowing day the front pages spoke volumes.”

Princess Diana received raves for her slicked-back look

Next year, coinciding with the 20th anniversary of Diana's death, a special exhibit celebrating the Princess' style will open at Kensington Palace. Diana: Her Fashion Story will open February 24, 2017 and will showcase a number of the royal's outfits including the pale-pink Emanuel blouse she wore for her engagement portrait and the infamous Victor Edelstein’s blue velvet gown, which she wore to dance with John Travolta at the White House.

“The exhibition will bring together an extraordinary collection of garments, ranging from the glamorous evening gowns worn on engagements in the Eighties, to the chic Catherine Walker suits that made up Diana’s working wardrobe in the Nineties,” a statement read. “The Princess’s relationship with her favourite designers will also be explored through a display of some of their original fashion sketches, created for her during the design process.”

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