The news broke a day before the wedding of the Duke and Duchess of Cambridge that "up-and-comer" Ellie Goulding would be performing at the reception.
Goulding's career was just taking off: she had lent her featherlight vocals to the 2010 John Lewis Christmas advert, covering Elton John's Your Song - the number that would soundtrack the Duke and Duchess's first dance - before releasing her debut album, Bright Lights, three months later. It topped the British album charts.
Eight weeks later she met Prince William at Radio One's Big Weekend in Bangor. She later told Billboard that grime musician Tinie Tempah: "introduced me to Prince William last year at a festival because they were both watching my set from the side of the stage. William enjoyed the set so much that he kept me in mind for, obviously, last week", she said, referring to the wedding.
Goulding performed around 14 songs at the reception, including covers of songs by The Wannadies, Stevie Wonder and The Killers, until her set finished at around 1.30am. She later described the event as "an amazing honour", saying: "The atmosphere was incredible and it is a night I will never forget."
While Harry was obviously at the event - he gave the Best Man's speech - there are no reports of the pair's fraternising. Goulding had been together with BBC Radio 1 DJ Greg James for eight months by this point, and picked up the Best British Female Solo Artist at the Brit Awards a few months earlier.
June 12, 2011: Harry, Goulding and Greg James share a table at the Polo
Just weeks after Goulding had performed at his brother's wedding, she was sandwiched between Harry and her then-boyfriend James at a charity Polo dinner in Berkshire.
Harry, then 26, was recently single after his relationship with Chelsy Davy, and hosted a charity dinner after the match in which he had played opposite William. One gossip website reported at the time that the younger Prince also "showed off his rippling torso as he braved torrential rain yesterday to take on the Duke of Cambridge in a charity polo tournament".
February 2012: Goulding starts dating Skrillex
Goulding reportedly broke up with James in January 12, although some reports suggest earlier, and their split was "amicable".
Although her relationship with Skrillex, born Sonny John Moore, wasn't reported until February 2012, Goulding and the Grammy Award-winning dubstep producer shared more than just matching hairstyles from the end of 2011, when they collaborated on Skrillex's Bangarang EP. The pair stayed together until October 2012.
20 September 2012: Goulding defends Harry's nude photographs
In the wake of Harry's nude poker photo scandal, Goulding stood by his side. She told New York radio station 92.3 NOW/New York: "He's young and he has fun just like all of us. And he should be allowed privacy and I think that was unfair.
"I hung out with him and he's a really nice guy. He takes his charity work really seriously and he takes his role really seriously as a prince, so it annoyed me a little bit that there was so much weird exposure about it.
"I don't think he needs to apologise at all; not a chance. It shouldn't have been published the way it was. And also, who took the picture? Who ever that was - bad friend," said Ellie, perhaps suggesting that she may have been a better one.
Goulding's interview came a month after the release of her single Anything Could Happen, following the news that summer that she would be releasing Halcyon, her second album, in November.
30 May 2013: Goulding serenades Harry at a charity dinner
Goulding, who was by this point dating War Horse actor Jeremy Irvine, performed at the South Pole Allied Challenge dinner to help Harry raise funds ahead of his trip there in November. She told The Telegraph: "I love performing for them all and Harry is great. What he's doing is brilliant."
Goulding performed at the closing ceremony for the paralympic games run by Harry. But all eyes were on what happened afterwards backstage.
Although neither Goulding and Harry were single, photographs of the pair happily hugging sparked rumours of romance. Goulding captured the event on her Instagram account, calling the Invictus Games "a huge success".
17 September 2014: Goulding performs at Harry's 30th birthday party
Giving a performance that possibly generated deja vous for many, Goulding was booked to perform at Harry's 30th birthday party, which had been rescheduled due to the Duchess of Cambridge's morning sickness.
According to The Sun, it was the Duchess who arranged for Goulding to play at the party. The tabloid wrote: "Kate knows Harry is a big fan of Ellie and wanted her to be part of the evening. It's a high compliment for her, especially because she is such a fan of Harry and the work that he does.
"Ellie said yes straight away and has agreed to perform whatever Harry fancies on the night. It's going to be a really intimate acoustic set. Harry will love it."
The news caused gossip websites to speculate that romance could be on the cards, but Goulding was seeing McFly musician Dougie Poynter at the time, and Harry was with charity worker Camilla Thurlow.
Kate knows Harry is a big fan of Ellie and wanted her to be part of the evening," an insider told The Sun. "It's a high compliment for her, especially because she is such a fan of Harry and the work that he does."
The source added: "Ellie said yes straight away and has agreed to perform whatever Harry fancies on the night. It's going to be a really intimate acoustic set. Harry will love it."
December 9, 2015: Goulding soundtracks Harry and Pippa Middleton's supposed first date
Things had been quiet on Ellie and Harry front for some time. She was recovering from the break-up with her longterm boyfriend Dougie and was giving her last arena shows before going on a career hiatus; he had been making a string of royal appearances after leaving the army in June.
But then OK! magazine caused much mirth by claiming that the prince was dating the Duchess's sister, Pippa Middleton. Their report seemed largely based on the admission of insider sources, but did involve Goulding - albeit only in recorded form. OK! claimed: Harry had prepared Middleton dinner, and had: "lit candles and put on some soft music he thought she'd like-Adele, Ellie Goulding, Bruno Mars. They sipped wine and then ate a pasta carbonara that he'd prepared himself."
Nearly two years after his charity dinner, and four after the Royal Wedding, Harry and Ellie reportedly sealed the deal under a blanket at the Audi Polo Challenge on Bank Holiday Monday.
Eyewitnesses speaking to The Sun told of "canoodling" between Goulding and Harry, who has allegedly told friends how fond he is of the singer.
The report said: "He has told friends how much he likes Ellie and she is clearly taken by him.
"They spent a lot of time sitting together under blankets."
One witness even claimed to have seen the pair kiss: "They were seen having a kiss before Harry had to go because he was playing polo the next day. Ellie left about five minutes later."