Surprise! Princess Kate gave a glam piano performance at Eurovision before Loreen won

LIVERPOOL, England − Swedish singer Loreen won Eurovision with her power ballad "Tattoo," but Princess Kate stole the show when she opened the competition with a surprise piano performance.

Kate paired with last year's winners, Kalush Orchestra, to perform their winning number, "Stefania," in a pre-recorded segment. Seated at a black grand piano in the Crimson Drawing Room at Windsor Castle, the Princess of Wales smiled as she performed, clad in a one-shoulder, bright blue gown, her skirt pooling on the red carpet. She wore her hair long in loose waves, accessorized with sparkling, dangling earrings.

The opening film, shot earlier this month, showed Kalush Orchestra singing and dancing in the Kyiv subway, with the tune picked up by musicians in the U.K., including Kate. The folk-rap band then emerged onstage in the Liverpool Arena on a giant pair of outstretched hands.

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The princess previously surprised royal watchers when she played at a televised Christmas concert at Westminster Abbey in 2021, performing alongside backup singers and a string section while Scottish singer/songwriter Tom Walker sang his holiday ballad "For Those Who Can't Be Here."

Loreen, who won the competition with her power ballad "Tattoo," beat acts from 25 other countries to take the continent's pop crown at the competition.

The diva from Stockholm previously won Eurovision in 2012 and is only the second performer to take the prize twice. "I am seriously overwhelmed," Loreen said. "This is so beautiful."

She said returning to the contest that helped make her a star was "like coming back to a family. We've had an 11-year-long relationship. We know each other by now."

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Finnish singer Käärijä, a wildly energetic performer whose rap-pop party anthem "Cha Cha Cha" won the public vote, finished second.

Israel's Noa Kirel came in third with power-pop anthem "Unicorn," while Italy's Marco Mengoni was fourth with his ballad "Due Vite" ("Two Lives").

It's Sweden's seventh time winning the contest, matching the record held by Ireland.

Britain hosted Eurovision this year on behalf of Ukraine, which won last year but couldn't take up its right to hold the contest because of the war. Air raid sirens sounded across Ukraine as the contest was underway.

Organizers said they turned down a request by Ukrainian President Volodymyr Zelenskyy to make a video address. The European Broadcasting Union said that would breach "the nonpolitical nature of the event."Eurovision bills itself as the world's biggest music contest. Competitors each have three minutes to meld catchy tunes and eye-popping spectacle into performances capable of winning the hearts of millions of viewers.

About 6,000 fans watched the show inside the arena, and tens of thousands more at big-screen events across the U.K. The global television audience has been estimated at 160 million.

Founded in 1956, Eurovision is a European cultural institution that has produced breakout stars − ABBA, Celine Dion and Måneskin are past winners − alongside performers whose careers sank without a trace.

Contributing: Kim Willis and Brian Truitt, USA TODAY, and Jill Lawless, The Associated Press