If you’re going to Taylor Swift‘s Eras Tour this week in Los Angeles or one of the nearly 100 shows still planned across the next year, you need to know this chant!

There are several chants that are shouted out by Taylor‘s fans during her concerts, but the most popular one is definitely “1, 2, 3, let’s go bitch.” (Here are some of the others!)

The chant happens right after the opening lines of the song “Delicate” and the origins of the chant date back to May 2018.

Keep reading to find out more…

Taylor first sings the opening verse, “This ain’t for the best / My reputation’s never been worse, so / You must like me for me / We can’t make any promises / Now can we, babe? / But you can make me a drink.”

Right after the word “drink,” fans chant “1, 2, 3, let’s go bitch,” leading into the change of the song’s beat with the lyrics, “Dive bar on the East Side, where you at?.”

The chant began after Emily Valencia, who was just 15-years-old at the time, shouted it out while attending the Reputation World Tour show in Pasadena, Calif. in May 2018. She shared the video on Twitter and it went viral, with the crowd and Taylor referencing it at shows within just weeks.

“It’s the weirdest thing, but that’s what happened,” Emily told BuzzFeed.

Taylor invited Emily to a Lover Secret Session in 2019 and greeted her with the chant.

“She was like, ‘I love performing “Delicate” now because you’ve changed it,’” she said.

Watch Emily‘s TikTok video documenting the history of the chant!