“Hats off to you Glastonbury,” says Shania Twain, surveying a sea of people – many of whom are, ironically, wearing cowboy hats.

“I feel and I see your support. Thank you so much for having me.”

Few artists have ever embraced Glastonbury’s so-called Legends Slot so fully.

The star has been talking up her appearance for months.

Not only did she share her ambition to arrive at the festival on horseback, but she convinced Great Western Railways to rebrand some of their rolling stock as “Shania Trains”.

On Saturday, she warmed up by taking a tour of Worthy Farm (“it’s a whole city”, she marvelled) and even cornered Friday night headliner Dua Lipa for a few tips.

Sadly, the festival thwarted her plan to put a stallion on the Pyramid Stage – but she arrived in style, nonetheless.

The 58-year-old was walked on stage by two drag queens and six dancers, holding aloft six brightly-coloured hobby horses.

Wasting no time, she launched straight into one of her biggest hits, That Don’t Impress Me Much.

As the audience joined her mockery of rocket scientists and Brad Pitt and men who own a car, the atmosphere was electric.

Twain looked incredible, with a rhinestone-studded cowboy hat, arm-length gloves and a black mini-dress, offset by a cascading pink cloak that she twirled around with camp abandon.

“This is amazing, because I can see everyone, everything, every flag,” she declared.

“I see a lot of cowboy hats and leopard print… and it’s really, really special.”

After that fantastic start, the energy dropped a little.

The crowd wasn’t as familiar with the next two songs, Don’t Be Stupid (You Know I Love You and You Win My Love.

And like Cyndi Lauper on Saturday, Twain seemed to be irritated by her earpiece.

But once her voice warmed up, that distinctive country twang came out loud and clear. Her throat sounded a bit dry and scratchy at times (Glastonbury has been really dusty this year) but the emotion was all there.

Twain’s booking was a touch of genius in a year where country has do-si-do’d back into the charts via Beyoncé’s Cowboy Carter, Kacey Musgraves’ Deeper Well and Shaboozey’s irresistible Bar Song (Tipsy).

In the 1990s, Twain was one of the genres first “crossover” stars, successfully fusing Nashville’s storytelling history to the bombast of stadium rock.

Her second album, The Woman In Me, went platinum 12 times over. The follow-up, 1997’s Come On Over, sold more than 40 million copies, thanks to empowering anthems like Man! I Feel Like A Woman and the mega-ballad You’re Still The One and

The latter was an early highlight of her Glastonbury set. Sitting down with an acoustic guitar, Twain asked the audience to sing the chorus with her.

“Normally my shows are at night and I can only see your reactions near the stage. But [today] I can see all of you, all the way to the back, right up to the tents,” she said.

“I can see you so well, but I want to hear you back as well.”

When she strummed the chords, the audience almost drowned her out.

It was a spine-tingling moment.

Before the show, the 58-year-old said she was a little “overwhelmed” at the idea of following in the footsteps of Dolly Parton, Diana Ross and Kenny Rogers in the coveted Sunday afternoon Legends slot.

“They are all people I consider to be music heroes and have been a big influence on my own career, so it’s surreal to have been invited,” she told BBC News.

“It’s been explained to me that it is a real event, a once in a lifetime thing. Everyone keeps going: ‘Let me tell you about it. Let me tell you about my experiences.’”

As the show continued, Twain began to realise just what that meant.

“I’m feeling frickin’ amazing,” she screamed at one point. “You guys are country music fanatics.”

The crowd stretched all the way to the back of the field – matching, but probably not surpassing, Coldplay’s audience on Saturday night.

And while Chris Martin had Tom Cruise and Stormzy watching his set, Twain got her own cast of A-listers, including model Cara Delevigne and Mad Max star Anya Taylor Joy.

Perhaps her set didn’t equal Kylie or Dolly in terms of surefire singalongs, but no sane person could have denied the response to her closing song – the aforementioned Man! I Feel Like A Woman.

By that point, Twain had given so much of herself that she gave up singing the melody, opting for a low-register harmony while her backing singers handled the high notes. (Her voice, it should be noted, has never been the same since Lyme disease caused nerve damage to her vocal cords in the early 2000s).

The audience, meanwhile, climbed on each other’s shoulders, swung their feather boas and screamed back every word in unison.

Afterwards, fans told the BBC they were much impressed.

“It was absolutely incredible. Best part of the weekend,” said Bethany from Surrey.

“I couldn’t have wished for anything more,” agreed Gloucester fan Liv. “She put on a fantastic show.”

“She was absolutely insane. I love her so much,” added Leah, from Middlesborough.

“At her age, she looks unbelievable, she’s got so much confidence.

“She is girl power, completely.”