USA Network(LONDON) — When Meghan Markle walks down the aisle in May to wed Prince Harry, all eyes will be on the wedding gown chosen by the 36-year-old American actress.

Markle became a global fashion trendsetter quickly after her relationship with Harry was made public.

Markle, a California native, will have to blend her personal style, which she has described as “California girl” and “relaxed,” with the formality of the royal family.

Here is what to know about Markle’s style and the tradition of royal wedding gowns as the countdown begins to Markle’s and Harry’s royal wedding.

Princess Kate’s and Princess Diana’s royal gowns

The same wedding designer guessing game took place for Kate’s 2011 nuptials and she did not disappoint.

Kate chose a stunning long-sleeved lace and ivory satin designed by Sarah Burton, the creative director at Alexander McQueen. The dress was both traditional and modern with a detailed back with a long train and buttons.

When Harry’s mother, the late Princess Diana, married his father, Prince Charles, in 1981 she wore a dress by husband-and-wife design team David and Elizabeth Emanuel.

The dress, which remained a closely-guarded secret until Diana’s wedding day, featured a 25-foot long train.

Who could design the dress?

At the top of the list to design Markle’s wedding dress is Misha Nonoo, a London-raised designer who reportedly introduced Harry and Markle and who has vacationed with Markle.

Nonoo, who designed the “husband” shirt Markle wore to the 2017 Invictus Games, was a finalist for the 2013 CFDA/Vogue Fashion Fund.

Nonoo has a showroom in New York that, combined with her British roots, would help satisfy critics on both sides of the Atlantic.

Jessica Mulroney, Markle’s longtime Toronto-based stylist, will no doubt be at Markle’s side advising her on the dress. While Mulroney, a bridal expert, is not a designer herself, she will likely be asked to weigh in on any decision.

Markle will also likely consider two of Princess Diana’s longtime favorite designers, Catherine Walker and Amanda Wakeley, for the honor of designing her wedding dress. Both designers have couture shops in London’s Chelsea district, not far from Kensington Palace, where Harry and Markle live.

Wakeley’s designs have been worn by the likes of Princess Kate, Jennifer Lopez, Kate Winslet and Angelina Jolie, but she is best known for her collaboration with Diana in the 1990s.

Walker is the designer most closely associated with Diana’s iconic style.

Markle and Harry have both said how it important it is that Harry’s late mother be included in their wedding. Markle’s engagement rings features two diamonds from Diana’s personal collection.

“It is days like – days like today when I really miss having her around and miss being able to share the happy news,” Harry said during the couple’s engagement interview. “But, you know, with the ring and with everything else that’s going on, I’m sure she’s, she’s with us.”

It would be a sentimental choice and a wonderful surprise for Harry if Markle were to choose one of Diana’s favorite designers.

“Obviously not being able to meet his mom, it’s so important to me to – to know that she’s a part of this with us,” Markle said at Nottingham Cottage last week in the engagement interview.

Another possibility to design Markle’s gown is Jenny Packham, one of Kate’s favorite designers. Packham, who has designed formal wear and gowns for Kate, has a good understanding of what type of dress would be required to meet the standards of a royal bride.

Fashion expert Joe Zee, who is a friend of Markle’s and interviewed her during New York City Fashion Week in 2015, said he expects Markle will wear a British designer and points to Erdem or Stella McCartney.

“She’s worn a lot of Erdem in the past, so it could be someone like him, but I’m putting my bets on Stella McCartney,” Zee said Tuesday on “Good Morning America.” “It most likely will not be [Alexander] McQueen because I feel like [Princess] Kate owns that.”

Markle wore a gown by Erdem Moralioglu, whose line was founded in London, when she accompanied Harry to a wedding in Jamaica in March.

Erdem, who was born in Canada to a British mother, has a wide following in the U.S., U.K. and Canada, making him a great choice as Markle’s wedding dress designer.

Markle also name-checked several designers when she spoke to Glamour last year about her dream wedding dress.

“Delphine Manivet and Christos Costarellos are faves of mine for their uniqueness and beauty,” she said. “And I will always be a fan of Elie Saab. J. Mendel is spectacular as well, especially for more structural designs.”

Markle told Glamour the Narciso Rodriguez-designed white dress Bessette-Kennedy wore to her 1996 wedding to John F. Kennedy Jr. is her favorite celebrity wedding dress, calling it, “Everything goals.”

Markle’s ‘perfect wedding dress’

Markle has been seen in a princess-like wedding dress before, when her “Suits” character, Rachel Zane, prepared to walk down the aisle last year.

The dress worn by Markle for the show was an Anne Barge wedding gown from Kleinfeld in Canada, Glamour reported at the time.

Markle told the magazine that she helped pick the dress for her character, calling it “classic and fairy tale,” but said that would not be the dress she would choose for herself.

“It’s not my personal style because I’m a lot more relaxed than Rachel but I love that I got to play dress up in this gown,” she said, adding her own personal style is “very pared down and relaxed.”

“Classic and simple is the name of the game, perhaps with a modern twist,” Markle said when asked her version of the “perfect wedding dress.” “I personally prefer wedding dresses that are whimsical or subtly romantic.”

‘A moment of fun and joy’

Harry and Markle will get married at St. George’s Chapel at Windsor Castle, a smaller venue than Westminster Abbey, where William and Kate tied the knot in 2011, and St. Paul’s Cathedral, where Prince Charles and Diana wed in 1981.

The choice of St. George’s Chapel as the wedding venue reflects Harry’s and Markle’s personal connection to the chapel. While Buckingham Palace is Queen Elizabeth’s official residence, she and Prince Philip have always called Windsor castle home.

Windsor Castle is also near where Harry spent his early years at Eton and Harry and Markle have spent private time getting to know one another away from the cameras at Windsor.

“It’s a bit smaller, it’s outside of London,” said ABC News royal contributor Victoria Murphy said. “That would just give them the opportunity to maybe have it a little bit more personal, a little bit more low-key, which is what Harry can obviously do, since he’s not going to be the king.”

Like any bride, Markle will choose a dress that reflects her own style and sensibilities. Holding the wedding ceremony at St. George’s Chapel could allow her to choose a dress that more closely fits the “relaxed” style she has described for herself.

Harry’s communication’s secretary, Jason Knauf, said Tuesday the couple wants their wedding day to be “fun” and reflective of their relationship.

“This wedding, like all weddings, will be a moment of fun and joy that will reflect the characters of the bride and groom,” he said.

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