Taylor Swift brought an extra dose of country to her Chicago, Ill. show on Saturday night (June 3), thanks to a surprise appearance from Maren Morris. Morris hopped onstage with Swift for a live rendition of "You All Over Me," which is a From the Vault track off of Swift's 2021 Taylor's Version of her Fearless album.

"We are so lucky, Chicago. We are so incredibly lucky," Swift told the crowd leading up to the song, "because not only did she agree to sing on the song with me, but Maren Morris is actually here."

Morris then took the stage to roaring applause, and before they began to perform, Swift pointed out that she and Morris hadn't shared a stage since the Reputation Tour. "The last time we did this was on the Reputation Tour. She came out and surprise guested with me," Swift remembered. "She's one of my favorite artists. I cannot wait to watch everything she does in her career. Everything she does is so thoughtful, and so brilliant."

With each woman strumming an acoustic guitar, the pair then launched into a simple, poignant rendition of "You All Over Me," coming together for gentle vocal harmony in the chorus of the song.

After the show, Morris shared a snapshot from the moment on her social media, including a photo of her and Swift laughing together onstage. "We finally got to play 'You All Over Me' and I won't ever be shutting up about it," she wrote. "Love you [Taylor Swift] and love you always, Chicago."

Morris and Swift's duet is one of six From the Vault additions to the 2021 version of Fearless. Also included on that list is a collaboration with Keith Urban, called "That's When." Fearless originally came out in 2008, and it was released while Swift was a country superstar, before she transitioned over to the pop world.

Swift's Saturday night show was her second stop in Chicago. The Eras Tour is scheduled to continue into August, where it will wrap with two dates in Los Angeles, Calif.

See the Most Played Country Song from the Year You Were Born

Who had the most played country song during the year you were born? This list is a fascinating time capsule of prevalent trends from every decade in American history. Scroll through to find your birth year and then click to listen. Some of these songs have been lost through the years, many of them for good reason!

Men named Hank dominated early before stars like Freddie Hart, Ronnie Milsap, Willie Nelson Clint Black took over to close the 1980s. More recently it's been Tim Mcgraw, Rodney Atkins, Kane Brown and Morgan Wallen. Did the most-played country song from the year you were born become a favorite of yours later? All info comes from Billboard's country airplay charts.

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