Princess Eugenie has pulled off a major surprise by choosing design duo Peter Pilotto after being widely expected to wear Erdem.
The bride stunned in the V-neck dress made from a jacquard of silk, cotton and viscose blend with a low back, designed to display the scars from her childhood operation for scoliosis designed by London-based Peter Pilotto and Christopher De Vos, who first met at the University of Antwerp.
The fabric of the dress - pronounced a "major departure" from the choices of previous royal brides by celebrity stylist Lucas Armitage - features symbols that are meaningful to the bride and groom, including thistles, to reflect their love for the Queen's beloved Balmoral estate in the Scottish highlands.
A design of shamrocks also featured a nod to the bride's Irish heritage, with Eugenie's maternal grandmother hailing from Ireland, where Fergie spent time while recovering from the aftermath of her divorce from Prince Andrew, the Daily Mail reports.
Pilotto and De Vos reinterpreted these symbols in a garland of rope like motifs, and once the artwork was completed, it was translated into a jacquard weave in the Como region of Italy and the intricate gown is estimate to have cost the Princess as much as £200K.
Hamish Shephard founder of Bridebook.co.uk told Femail: "We believe the dress to have cost in the region of £175-200,000 (NZ$354-404,000). Everything about it has been made completely couture, especially for Eugenie, which is a vast amount of work.
"It incorporates a bespoke fabric, of which there are several metres because of the length of the train, which would have taken hours upon hours to design and then hand-make.
"The structure of the dress has also been made bespoke, specifically to complement and flatter her figure perfectly. The bespoke corset, structured bodice and skirt would all have been fine-tuned over several fittings, until the perfect fit was achieved."
However, other estimate that Eugenie's cost have cost more than £200K, making it more expensive than even the estimated cost of Meghan Markle's Givenchy creation.
"The dress Eugenie has worn for her nuptials is a work of wearable art. The nature and complexity of the bespoke fabric the construction and amount of details also comes with the price tag of a work of art.
"There's bespoke fabric in vast quantities - I'd expect 20 metres at least, all hand embroidered and the under dress - the framework for the orgami style skirt to sit on.
"Due to nature of the dress I would think this would be the most expensive royal bridal gown we have seen in years."
Princess Eugenie met the designers when she was co-hosting an event in support of women artists. Her Royal Highness has been wearing designs by the brand for several years.
Princess Eugenie, Pilotto and De Vos have worked closely together on the design of the dress. The designers undertook archive research into previous dresses worn by Members of the Royal Family and identified a silhouette.
Buckingham Palace revealed that the bride had several fittings, during which the dress was developed layer by layer, constructing it from the corset and the complex underskirt to the fitted bodice and full pleated skirt.
'"The low back feature on the dress was at the specific request of Princess Eugenie who had surgery aged 12 to correct scoliosis," the palace said in a statement.
The Queen's granddaughter was diagnosed with scoliosis and underwent corrective surgery that saw a pair of eight-inch titanium rods inserted alongside her spine.
She has invited the doctor who performed the life-changing operation to her big day and didn't try to hide her scars as she walked up the aisle this morning.
"It incorporates a bespoke fabric, of which there are several metres because of the length of the train, which would have taken hours upon hours to design and then hand-make."
The Princess, 28, said: "I think you can change the way beauty is, and you can show people your scars and I think it's really special to stand up for that."
Eugenie previously told how her wedding would be an environmentally friendly, anti-plastic affair.
"(The dress) is the one thing that I was really decisive about," the princess told British Vogue magazine in an interview in the run up to her big day.
"As soon as we announced the wedding, I knew the designer, and the look, straight away. I never thought I'd be the one who knew exactly what I like, but I've been pretty on top of it."
In her engagement interview in January, she told the BBC's Matt Baker that her only stipulation was "no meringue shoulders", calling them "unfashionable".
Before today's ceremony, Paddy Power had suspended betting on Eugenie wearing Stella McCartney after a flood of bets.
The British designer created the Duchess of Sussex's halterneck evening gown, which she wore for the wedding afterparty at Frogmore House when she married Prince Harry in May.
A Paddy Power spokesman said before the wedding: "We've seen a lot of action on Stella McCartney to be the designer of Princess Eugenie's wedding dress this morning, forcing us to stop taking bets.
"The level of wagers could indicate insider knowledge, and the brand seems a good fit for the day with their positive environmental standpoint."
Eugenie was walked up the aisle by her father, the Duke of York, in front of 850 guests including the Queen and a host of A-listers - from supermodels Kate Moss and Naomi Campbell to the A-list actress Demi Moore.
Commenting on Eugenie's style evolution this week, Sassi Holford - who famously designed Autumn Phillips' wedding gown - said: "I think Eugenie's style has changed in the last five years.
"She's 28 now, I think she's at that age where you start to develop that core style.
"And things have simplified. So I'd be surprised if it's Vivienne Westwood, I think she'll probably go for cleaner lines. Certainly the dress she wore to Meghan's very clean lines, understated. I think she's gonna nail it.
"I think there could possibly be a second dress, with Kate and Meghan the point of the second dress was that both their [day] dresses had sleeves.
"And then they went on to have a less formal party with their friends.
"So if [Eugenie's] dress has sleeves I think there will be a second dress so she can party with her friends later on."