Taylor Swift and Calvin Harris were introduced by mutual friend Ellie Goulding at the ELLE Style Awards 2015 after party on February 24, 2015.
Dating rumors started on March 3, 2015. According to sources, they began flirting with each other quickly after they first met. People speculated that Calvin broke up with his girlfriend Aarika Wolf to date Taylor.
Taylor and Calvin started dating officially on March 6, 2015.
Their relationship was mostly speculation as they were seen out in Nashville and at concerts in LA.
Their first public appearance as a couple was at the Billboard Music Awards on May 17, 2015.
They have since been very open about their relationship and seem comfortable enough with each other to post about it numerous times on social media.
It was rumored they broke up in October 2015, but those rumors were not true, Calvin denied them on twitter.
In December 2015, Calvin joined Taylor's family for a snow trip, which was documented by Taylor through her Instagram.
When Taylor won big at the Grammy Awards 2016 in February, Calvin posted a tweet congratulating his "beautiful girlfriend" on her awards.
On their one year anniversary on March 6, 2016, Calvin gifted Taylor with a gold locket with the date engraved on it. The following week they took a vacation to a tropical location, posting multiple Instagram photos after the trip.
During the 2016 iHeart Radio Awards, Taylor thanked Calvin for being "the most amazing person to come home to" after the lights dimmed and the crowds were gone. In this speech, Taylor refers to Calvin by his real name, Adam.
Taylor attended Coachella for the first time to support Calvin as a headlining artist.
Taylor and Calvin were seen together for the last time on May 19, 2016.
They broke up in late May 2016, after 1 year and 2 months together. Their break-up was confirmed on June 1, 2016. On June 2, 2016, Calvin confirmed the break-up rumors via twitter, "The only truth here is that a relationship came to an end & what remains is a huge amount of love and respect." and Taylor retweeted his tweet. Calvin deleted the tweet shortly after.
Photos of Taylor and rumored new boyfriend Tom Hiddleston snogging on a rock in Rhode Island surfaced on June 15, 2016, thanks to British tabloid The Sun. Calvin does some spring cleaning on social media and unfollowed his ex and her brother Austin Swift. He also reportedly blocks a bunch of Swifties. In a since-deleted tweet, Calvin writes, "Oh boy it's about to go down" along with three skull emojis.
On June 16, 2016, Calvin and Taylor deleted nearly all traces of each other from their respective social media accounts.
On June 29, 2016, Calvin snapchats from his vacation in Cabo. A bevy of women enjoy the sunset with him. The caption was a shade to Taylor as he said, "I write songs."
On July 7, 2016, TMZ reports that Calvin is set to release "Olé," a new song that's allegedly about Taylor cheating on him. Lyrics include: "I see online that you begun to be a good girl and take trips with your boyfriend. Being attentive, continue to pretend..." Us Weekly later quotes a Taylor source saying the song was recorded during pre-Hiddleswift days. However, Taylor never cheated on Calvin since acording to sources she began dating Tom about 2 weeks after her split from Calvin.
On July 13, 2016, TMZ reports that Taylor and Calvin broke up because of everything that happened with songwriting credits on his summer hit, "This Is What You Came For." Taylor initially penned the song and recorded a demo with Calvin. Sources say that when the track was released in April, Taylor's credit appeared as her pseudonym "Nils Sjöberg" and on that same day, Calvin said in a radio interview that he and Taylor "haven't even spoken about" collaborations.
Taylor's rep confirms to People that she wrote "This Is What You Came For" under a pseudonym. Calvin responds in an epic series of tweets that references everything from Taylor's personal life to her free time to Taylor's rumored nemesis Katy Perry.
On September 7, 2016, Calvin talked about his split from Taylor in a new interview with British GQ.
"It's very difficult when something I consider so personal plays out very publicly," Harris says, speaking about the demise of his and Swift's relationship in depth for the first time. "The aftermath of the relationship was way more heavily publicized than the relationship itself. When we were together, we were very careful for it not to be a media circus. She respected my feelings in that sense."
"I'm not good at being a celebrity," he adds.
Harris specifically talks about his infamous Twitter rant about Swift in July, when news broke that the 26-year-old singer wrote Harris and Rihanna's summer hit, "This Is What You Came For," under the pseudonym Nils Sjoberg, when the two were still a couple. "Hurtful to me at this point that her and her team would go so far out of their way to try and make ME look bad at this stage though," he tweeted at the time, before going on to call out her relationship with actor Tom Hiddleston. "I figure if you're happy in your new relationship you should focus on that instead of trying to tear your ex bf down for something to do."
Harris now calls his Twitter takedown "completely the wrong instinct."
"I was protecting what I see as my one talent in the world being belittled," he explains. "When it ended, all hell broke loose. Now I see that Twitter thing as a result of me succumbing to pressure. It took me a minute to realize that none of that matters. I'm a positive guy."
As for their breakup itself, Harris appears to be at peace with the split.
"For both of us it was the wrong situation," he shares. "It clearly wasn't right, so it ended, but all of the stuff that happened afterwards..."
On September 9, 2016, Taylor sings along to “This Is What You Came For,” a song played during BFF Gigi Hadid’s fashion show with Tommy Hilfiger during New York Fashion Week. Taylor is so into the song/moment that she posts a video of her sing-along on Instagram.
Calvin, who does not follow Taylor on Instagram, joins the one million or so fans who like the video, causing many to believe that their post-breakup drama is over.
On September 16, 2016, Calvin releases a new song, “My Way,” featuring his own vocals. With lyrics such as “Why wait to say, at least I did it my way” and “Lie awake, two faced,” the Internet quickly identifies the song as a post-breakup song about Taylor.
Speaking to iHeartRadio, Calvin says the song is about “breaking out of a situation that you thought was a good thing” and that this is probably his last release of the year.
On November 1, 2016, country group Little Big Town revealed on Facebook Live that their new single, "Better Man," which was released on October 20, 2016, was written by none other than the "Shake It Off" singer. "[Swift] sent us this song and it was one that was very special to her," Karen Fairchild said.
While the timing of when Swift wrote the track isn't known, the lyrics are pretty telling for someone who has called it quits with both Calvin Harris and Tom Hiddleston this year. "I know I’m probably better off on my own than lovin' a man who didn’t know what he had when he had it," Swift's lyrics read. "And I see the permanent damage you did to me/Never again, I just wish I could forget when it was magic."
The chorus is also pretty vulnerable. "Sometimes, in the middle of the night, I can feel you again," Little Big Town sings. "But I just miss you, and I just wish you were a better man."
Two days after the release of "Better Man," Swift gave her first performance of 2016 in Austin, Texas, and decided to sing "This Is What You Came For."
"As a songwriter, the most rewarding feeling in the world is writing something and then having a crowd sing it back to you, because they know the words. It’s the coolest thing in the world," she told the audience before jumping into her solo piano rendition of the electronic hit. "And I've never played this song live before, but you know it. Maybe you could sing along, and then I could get to know what that feels like to hear it sung back to me."
On August 27, 2017, Taylor Swift released the music video for her brand new song "Look What You Made Me Do" — Swift hid many messages in her "Look What You Made Me Do" music video—some more obvious than others. We see the aforementioned tombstone, where Swift’s reputation lies, but also a second one, reading “Nils Sjoberg”, the pseudonym Swift used as a co-writer on her ex-boyfriend Calvin Harris’s song, This Is What You Came For, a collaboration widely assumed to have contributed to their breakup.
But perhaps her most brutal was another very subtle reference to Calvin Harris himself: Some eagle-eyed fans on Tumblr (via Buzzfeed) spotted, in the opening shot of Swift in the tub, jewelry strewn beside her that spells out "no."
One of the necklaces looks quite a bit like the locket Harris gave Swift on their one-year anniversary. Later in the video, there's an empty engagement ring box. Some fans connected the "no" and believe Swift may be saying she rejected Harris's proposal—or at least, the prospect of marrying him further down the line by ending things when they did last summer.
And this may not be too far off from reality, interestingly: Right when their break-up was publicly announced in June 2016, Page Six reported that Harris had been ring shopping, that it could've gone there. "She broke up with him this week," a source told the outlet at the time. "She gave a bulls–t excuse about her career. He was ring shopping."
Harris, who had a drama-filled breakup aftermath with Swift last year, reportedly didn't clap when the "Look What You Made Me Do" video played at the VMAs. Perhaps this was one of the reasons.