BALTIMORE: Oprah Winfrey seemed a tad confused about her seating assignment.

Serena Williams documented her journey to St. George’s Chapel on Instagram. Idris Elba smiled broadly as he escorted his fiancee, model Sabrina Dhowre, who wore the obligatory hat.

They were among a slew of celebrities among the 600 guests Prince Harry and Meghan Markle invited to their wedding ceremony on Saturday, an event from which politicians were excluded.

Several of Markle’s former co-stars on the USA Network paralegal drama “Suits” were invited. Among them were Gina Torres, Sarah Rafferty, Abigail Spencer, Rick Hoffman and Markle’s on-screen hubby, Patrick J. Adams. “Pretty Little Liars” star Troian Bellisario, Adams’ wife, was his plus-one.

Indian actress Priyanka Chopra, a friend of the bride’s, strutted into the chapel in a light heather grey Vivienne Westwood pencil skirt and matching jacket with an asymmetric collar.

Tennis star Williams, accompanied by her husband, Reddit co-founder Alexis Ohanian, chose a blush, long-sleeve silk drape dress by Atelier Versace to go with her fascinator in pale pink, a hue also favored by Winfrey and others for the royal wedding.

Elton John, looking dapper in tails, did double-duty as a wedding guest and a performer at the luncheon reception hosted by Queen Elizabeth II. He sported pink eyeglasses as he arrived with husband David Furnish.

John was a close friend of the groom’s late mother, Princess Diana, and played his hit “Candle in the Wind” at her 1997 funeral. Kensington Palace did not disclose which songs he chose for the wedding.

George and Amal Clooney, James Corden and David and Victoria Beckham also watched the nuptials on the grounds of Windsor Castle — Ms. Clooney in a bright yellow Stella McCartney dress and matching hat. It seemed her hubby walked just slowly enough to keep her out of peril in her heels on the castle’s menacing cobblestones.

British singer James Blunt was in traditional tails, while Argentine polo player Nacho Figueras went for a double-breasted blue suit. He didn’t forget the pocket square.

Actress Carey Mulligan shined in an all-over yellow floral print dress with a high neck and short sleeves from Erden. She was accompanied by husband Marcus Mumford of the Mumford & Sons band.

Joss Stone was also on hand, prompting BBC commenters to note that the singer, often barefoot on stage, wore shoes.

Oprah’s longtime partner, Stedman Graham, said he could have joined her, but was happier giving a commencement address inside a gymnasium in Baltimore, where his advice to graduates just might extend to a certain American across the pond: Don’t be concerned with how others define you, he said: “The only thing that matters is how you define yourselves.”