Taylor Swift and Katy Perry: A timeline of their feud

Katy Perry and Taylor Swift fans probably never thought they'd see their idols on speaking terms, let alone baking terms, but that's exactly what's happened this week.

Perry, who spent several years falling out with the Shake It Off singer, shared a picture of some cookies with "peace at last' written on the plate on Tuesday night.

She tagged Taylor in the post and captioned it "feels good", while Taylor commented with 13 heart emojis.

But wait, didn't they already make up a year ago when Katy gave Taylor an olive branch?

It's been a long and complicated feud, with fans now hoping a collaboration could be in the works.

Here's a full timeline of how it all unfolded:

Katy and Taylor were seen together at awards ceremonies hanging out with other stars, giggling and having fun.

In July 2009 Taylor Swift tweeted: "Watching the Waking up in Vegas video. I love Katy Perry. I think I'm going to hang her poster on my wall now."

Katy replied: "You're as sweet as pie! Let's write a song together about the subject we know best...for my new record. It'll be brilliant."

They were definitely mates.

They even sang Katy's song "Hot N Cold" on stage together during Taylor's Fearless tour.

Not only did Taylor duet with Katy during her Fearless tour but also with John Mayer and it's rumoured the two dated.

It was never confirmed but Taylor did release a song called "Dear John" with lyrics that included: "It was wrong, don't you think nineteen's too young to be played by your dark, twisted games when I loved you so."

Ouch.

A couple of years later Katy Perry is seen getting close to John Mayer.

It's not clear if this was the start of when things went wrong between the two but in 2014 they definitely did.

By this time Taylor Swift was on her way to becoming a massive pop star - she won a Grammy for her single "I Knew You Were Trouble."

She also went on a world tour - the Red Tour - and hired three dancers who had danced for Katy Perry.

A few months later Katy Perry was also going on a world tour and there are claims that those dancers approached Katy to ask if they could join her Prism tour but it would mean they'd have to leave Taylor's tour half-way through.

They agreed to do it.

That's when the rumours started that the two had fallen out, and ahead of the release of Taylor's fifth album and the single Bad Blood we knew more about the feud.

Taylor Swift did an interview with Rolling Stone magazine and talked about how Bad Blood was about another female pop star, saying the person did something "so horrible" that made them "straight-up enemies."

She got more specific: "She basically tried to sabotage an entire arena tour. She tried to hire a bunch of people out from under me."

Straight after that article, Katy Perry posted a cryptic tweet about Regina George - the villain of the 2004 comedy Mean Girls.

Katy spoke about the tension between the two stars in a Carpool Karaoke interview with James Corden.

"She started it, and it's time for her to finish it," Katy said.

Katy's song Swish, Swish is also said to be about the feud with Taylor Swift.

In 2017, Katy then apologised to Taylor during a 24-hour YouTube live stream ahead of her album Witness being released last year.

"I'm ready to let it go," she said in an interview.

"Absolutely, 100%. I forgive her, and I'm sorry for anything I ever did, and I hope the same from her, and I think it's actually - I think it's time."

Katy Perry sent Taylor Swift an actual olive branch, seemingly ending the beef between the two megastars.

Swift shared a video of the package she received from Katy - which appeared to include a note with the words "miscommunications" and "deeply sorry" written on it.

The olive branch is a symbol of peace.

But maybe the olive branch wasn't enough because this picture of a plate of cookies with "peace at last' written in red seems to officially indicate they are friends.

Katy added a caption "Feels good" tagging Swift.

It's also proof that the two are hanging out together because keen fans have spotted the photo was taken in Taylor Swift's kitchen.

The feud is over.

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