Smash hit

But the egalitarian conformity of Swedish society, a deep national distaste for flashing one’s cash around, created its own pressures. It was public knowledge, for example, how much Abba made. “It was in the papers constantly,” says Ulvaeus. “When they wrote about the Stones, they’d talk about the music or Keith Richards being drunk. But with us, half of it was about money. I got so fed up.” At the time the Swedish tax system was so punitive that Astrid Lindgren, author of children’s classic Pippi Longstocking, complained she was paying 102 per cent of her income.

After his divorce, Ulvaeus planned to be a playboy, but instead met Lena Källersjö, his second wife, within a week. With Abba over, he decided to move to England. “English people are so much more varied and exciting than Swedish people,” he said at the time. Fancying the life of a country squire, he and Källersjö bought a house with 16 acres in Henley-on-Thames, sent their two children to English private schools, and tried to keep sheep. “It wasn’t quite the idyll we thought. So many die. I ended up having a lamb lying on my chest to try to keep it alive one night because the mother had left it. But it died, sadly. After that I didn’t want sheep any more.”

His career was not in the best health either. He and Andersson had hoped that their musical, Chess, would lead to a Rice/Lloyd Webber-style theatrical career, but instead it tanked, closing on Broadway after three months. “That was a real low in my professional life, in the rest of my life too,” says Ulvaeus.

Throughout the Eighties, Abba were just a joke, a symbol of the naff, over-blown Seventies. It was the mid-Nineties before the fashion wheel rotated and Abba were the soundtrack of two films, The Adventures of Priscilla, Queen of the Desert and Muriel’s Wedding. Both celebrated the songs’ camp drama, but at the same time a new generation of musicians started to appreciate the music itself.

Erasure released its album Abba-esque and Andersson and Ulvaeus were tickled when the Fugees asked to sample The Name of the Game on Rumble in the Jungle. “This funky rap group from America, they want a riff from the square Scandinavians? We thought, ‘That’s wonderful. They can have it!’” But by the time Madonna asked to use the twirling, twinkling refrain from Gimme Gimme Gimme in Hung Up they had grown canny and demanded half the royalties. Ulvaeus chuckles: “You bet we did!”

Now Abba have become a musical national treasure, beloved by all ages. “Young people download music indiscriminately. They aren’t concerned when it was made,” says Ulvaeus. “It’s simply, ‘I like that,’ or, ‘I don’t like that.’” So quality will out? “I like to think so.”

Mamma Mia! began 12 years ago when producer Judy Craymer suggested an Abba musical. Though all concerned are astonished at its success, they put it down to pure, unashamed escapism. Indeed, Meryl Streep took a bunch of friends to the Broadway production to cheer them up after 9/11 and was ecstatic to be offered the lead in the movie. “We hardly dared approach her at first,” says Ulvaeus. “We knew she could sing, but had no idea quite how well. She recorded The Winner Takes it All in one go. I bet Barbra Streisand or Céline Dion would have done it in pieces.”

He is generous, too, about Pierce Brosnan, much ridiculed for gargling through SOS: “He hits the notes without problem. He has a nice kind of folky Irish feel that Benny and I found attractive.”

Yet the powering force behind Mamma Mia!’s success is the women: unusually, the director, producer and writer of the show are all female, as are most of the cast and, of course, the fans who return to see it time after time. “You know, this is the one of the only films about women in their fifties,” remarks Ulvaeus. “I think writing for Agnetha and Anni-Frid I somehow must have developed an instinct for what women want.”

Mamma Mia! The Movie is available to own on Blu-ray and DVD from November 24

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