The Queen’s granddaughter, who was accompanied by her proud father the Duke of York, waved to crowds as she arrived at the West Steps in the 1977 Rolls Royce Phantom VI, which belongs to the Queen.
Ninth in line to the throne Eugenie’s gown features a neckline that folds around the shoulders to a low back that drapes into a flowing full length train.
The low back feature was specifically requested by Eugenie, who had surgery aged 12 to correct scoliosis, Buckingham Palace said.
The dress also includes a number of symbols that are meaningful to the bride as motifs, including a thistle for Scotland acknowledging the couple’s fondness for Balmoral, a Shamrock for Ireland as a nod to the bride’s Ferguson family, and the York Rose and ivy representing the couple’s home.
Eugenie is also wearing the Greville Emerald Kokoshnik Tiara, made in 1919 in the fashionable “kokoshnik” style popularised in the Russian Imperial Court, which was lent to her by the Queen, along with diamond and emerald drop ear-rings, a wedding gift from the groom, and satin peep-toe heels by Charlotte Olympia.
Her husband-to-be Jack was waiting at the altar, alongside his best man and brother Tom Brooksbank.
Princess Charlotte waved to the crowds as she arrived with Eugenie’s gaggle of bridesmaids and pageboys, who also included Prince George and Theodora Williams - daughter of pop star Robbie Williams and Ayda Field.
The others were Zara and Mike Tindall’s spirited four-year-old Mia, Peter and Autumn Phillips’s daughters Savannah and Isla, Eugenie’s goddaughter Maud Windsor, and family friend Louis de Givenchy.
The Queen, the Duke of Edinburgh, the Prince of Wales, the Duke and Duchess of Cambridge and the Duke and Duchess of Sussex were among more than 40 royals gathered in the chapel’s Quire to witness the ceremony.
A star-studded congregation of 800 guests included Hollywood actresses Liv Tyler and Demi Moore, supermodels Kate Moss and Naomi Campbell, singers Ricky Martin, Ellie Goulding and James Blunt, actor Stephen Fry, and artist Tracey Emin, as well as Williams and Field.
Meghan, dressed in a navy dress and coat by her wedding dress designer Givenchy, and Harry were returning to the chapel just five months after they pledged their love for one another in the same Windsor Castle venue.
Two of Harry’s exes, Cressida Bonas and Chelsy Davy, are also attending.
Eugenie hinted in an ITV interview that she would show the scars from the operation she underwent as a child.
She 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.”