Taylor Swift and then One Direction's member Harry Styles met at the 2012 KCAs on March 31, 2012. It was then that they had a short fling. However, they broke it off after Styles was papped kissing model Emma Ostilly in New Zealand, in late April.

Over the months, Styles was linked to a couple of other girls while Swift spent summer with Conor Kennedy. After Taylor's relationship with Conor ended, Harry and Taylor reunited at the VMAs on September 6th. After the awards, they went to a seafood restaurant in Los Angeles with Ed Sheeran and a couple of other friends.

In early October, Swift let it slip at Jonathan Ross Show that she was dating a "good-looking" boy. She's later spotted hanging out with Styles at TCAs backstage. By early November, she was already being spotted wearing a paper airplane necklace identical to Styles' famous paper airplane necklace. In November 15th, Harry went to the X Factor USA to watch Taylor's rehearsal and performance; they were spotted flirting backstage. Later that month, Seventeen magazine shared an article revealing that, a few months earlier, Harry talked about Taylor during an One Direction 'Seventeen Magazine' interview.

While talking about Swift, he 'gushes' over her: "[Taylor]'s a really lovely girl. Honestly, she couldn't be a sweeter person," Harry told Seventeen. "She's a great girl and she's extremely talented." He went on to describe Taylor as "one of those people you meet [who's] genuinely a nice person. Some people you meet and they are not as nice as you make them out to be, but she's one of those people who's really just amazing."

Their first public date was at the Central Park in December 2nd, and that spiraled into a crazy month of outings in New York City, London, and Utah. Swift spent her 23rd birthday with Styles at his hometown, Cheshire, where she met his family. They brought in the new year with a kiss at Times Square after Taylor's performance at Dick Clark's New Year's Rockin' Eve.

They were on vacation together to the British Virgin Islands on January 2, 2013, however it was quite a short trip as they supposedly got into a massive argument and broke up, leading to Taylor leaving the islands alone earlier than planned.

For most of 2013, their relationship seemed to be sour with Taylor mocking Harry at the GRAMMYs by making fun of his British accent on her performance, later at the BRIT Awards implying that she wrote "I Knew You Were Trouble" about him, and then again at the VMAs where she apparently threw a shade at him after wining an award for the same song. However, Swift and Styles were caught hanging out at the VMAs after party with Ed Sheeran and other friends.

In 2014, it seems that they have resolved their issues and are good friends, or at least amicable towards each other. In late 2014, Taylor released her album "1989" with a load of songs about Harry, all relatively good in spirit, which had never happened back then, except when she wrote an apology to an ex, Taylor Lautner.

These songs included "Style," "Out Of The Woods," "All You Had To Do Was Stay," "I Know Places," and "Clean" among others. Taylor shared a lot of details on their on-and-off relationship in these songs: implies that Harry went after her while being in a casual relationship with Kendall Jenner (in "Style"), mentions the paper airplane necklace and also an snowmobile accident that they got into back in Utah, that resulted in Styles getting twenty stitches on his chin ("Out Of The Woods"), and how the media invasion and public scrutiny was the main reason why their relationship didn't work ("I Know Places" and "Wonderland").

They were seen together at an after party for the Victoria's Secret Fashion Show in December 2014, and also at Caleb Followill's birthday party in January 2015. In February 2015, Taylor released the music video for "Style" where she is shown holding Harry's paper airplane necklace numerous times. At the New Year's Eve, on December 31st, she released a music video for "Out Of The Woods" where she appears running from wolves; in the music video, she throws away Harry's paper airplane necklace.

In April 2017, Harry publicly talked about his relationship with Swift for the very first time during an interview for Rolling Stone, "When I see photos from that day [their Central Park date on December 2, 2012]," he says, "I think: Relationships are hard, at any age. And adding in that you don't really understand exactly how it works when you're 18, trying to navigate all that stuff didn't make it easier. I mean, you're a little bit awkward to begin with. You're on a date with someone you really like. It should be that simple, right? It was a learning experience for sure. But at the heart of it – I just wanted it to be a normal date."

He's well aware that at least two of Swift's songs – "Out of the Woods" and "Style" – are considered to be about their romance. ("You've got that long hair slicked back, white T-shirt," she sang in "Style.") "I mean, I don't know if they're about me or not..." he says, attempting gallant discretion, "but the issue is, she's so good, they're bloody everywhere." He smiles. "I write from my experiences; everyone does that. I'm lucky if everything [we went through] helped create those songs. That's what hits your heart. That's the stuff that's hardest to say, and it's the stuff I talk least about. That's the part that's about the two people. I'm never going to tell anybody everything."

Fans wondered whether "Perfect," a song Styles co-wrote for One Direction, might have been about Swift. "And if you like cameras flashing every time we go out/And if you're looking for someone to write your breakup songs about/Baby, I'm perfect."

Was he able to tell her that he admired the songs? "Yes and no," he says after a long pause. "She doesn't need me to tell her they're great. They're great songs... it's the most amazing unspoken dialogue ever."

Is there anything he'd want to say to Swift today? "Maybe this is where you write down that I left!" He laughs, and looks off. "I don't know," he finally says. "Certain things don't work out. There's a lot of things that can be right, and it's still wrong. In writing songs about stuff like that, I like tipping a hat to the time together. You're celebrating the fact it was powerful and made you feel something, rather than 'this didn't work out, and that's bad.' And if you run into that person, maybe it's awkward, maybe you have to get drunk... but you shared something. Meeting someone new, sharing those experiences, it's the best shit ever. So thank you."

Harry Styles' self-titled solo debut album was released a month after his interview to Rolling Stone came out – a particular song in the album called "Two Ghosts" was linked to their romance and seen as a response to Swift's "Style." "Same lips red, same eyes blue/Same white shirt, couple more tattoos/But it's not you and it's not me"

In November 2021, Swift released her "Red" album re-recorded version which includes "vault songs" such as "Message in a Bottle" and "The Very First Night" that were immediately associated to Styles, as these songs were written back in 2012 and there's multiple parallels to Swift's "1989" songs lyrics. Swift's fans also theorizes that she may have written "Treacherous" and "Come Back... Be Here" about their early 2012 fling.