It was the same setting as the wedding of Harry and Meghan earlier in the year, and the Duke and Duchess of Sussex, as the couple are now known, were among the star-studded congregation at Friday's event.
The nuptials have drawn most senior members of the royal family, including Eugenie's grandmother, Queen Elizabeth II, who will host a champagne luncheon for the newlyweds shortly after the ceremony.
Kate chats to Prince Harry and Meghan.
Eugenie is a director at London's Hauser & Wirth art gallery, and Brooksbank owns a wine wholesale business and is European brand manager for Casamigos Tequila, which was co-founded by US actor George Clooney. This has led to raised eyebrows over the couple's decision to copy Harry and Meghan with an open-topped carriage ride through Windsor, requiring road closures and an estimated £2m policing bill.
There were occasional blue skies on a generally cloudy, gusty day as the royal standard flew atop the Windsor Castle complex, indicating the queen was in residence.
Robbie Williams' daughter, Theodora, pictured as bridesmaid.
Easily one of the proudest moments in any mother's life, Sarah Ferguson, Duchess of York was beaming as she arrived for the wedding of her second daughter.
There has been doubts about whether the 97-year-old Philip would be well enough to attend, but he seemed to be in good form during a rare public appearance.
Eugenie's sister, Princess Beatrice, will read a passage from "The Great Gatsby".
The ceremony will be broadcast on British TV and live-streamed on the Royal Family and Prince Andrew's YouTube, Facebook and Twitter channels. "But there's something different about Friday's royal wedding, and people aren't happy".
"Most Brits opposed taxpayer funding of Prince Harry's wedding but as with all royal events were forced to accept it", a spokesman for the group said. Eugenie, ninth-in-line to the throne, has copied much of her cousin's blueprint for her big day.