For an album that its main creator didn’t really like, Nirvana’s 1991 release, Nevermind, did pretty damn well. For Kurt Cobain, probably too well. Ultimately selling more than 30 million copies worldwide, it unwittingly catapulted him and his two goofball bandmates – Krist Novoselic and Dave Grohl – into a world of international celebrity they weren’t sure they wanted, and provided Cobain enough money to feed the demons of his childhood and chronic stomach pain with heroin.

Cobain, though, was highly critical of Nevermind; its blend of anguished yelping, grating guitars, melodic hooks and rock-solid drumming might have caught on with the masses and launched the media-driven ‘grunge’ phenomenon, but Cobain felt its slick production and somewhat commercial sound was at odds with the independent punk rock scene of which he was still very much a part.

For all his protests about its success – “I’m embarrassed by it now. It’s closer to a Mötley Crüe record than it is a punk rock record” – to his issues with the macho fans the album attracted, Nevermind is still an album being listened to today. In fact, so strong is its legacy that, to celebrate this month’s 20th anniversary of its release, a special exhibition, In Bloom: The Nirvana Nevermind Exhibition at The Loading Bay Gallery at Brick Lane, will be held to mark it.

Featuring rare and treasured artefacts, including rarely seen photographs, lyrics, tour posters, fan memorabilia and interactive displays, it will also showcase a replica stage, complete with instruments, from Nirvana’s 1991 Halloween concert at Seattle’s Paramount Theatre.

It’s hard to think what Cobain, who killed himself with a shotgun blast to the head in 1994 aged 27, would have made of it all. One thing’s for sure though, when he wrote Nevermind, he never realised just how his life dramatically his life would change.

Filmmaker David Markey (wegotpowerfilms.com) was on tour in Europe with Nirvana and Sonic Youth in 1991, filming what was to become The Year Punk Broke, in the months before Nevermind’s explosion. He confirms no one on tour had an inkling of the success to follow, especially Nirvana themselves.

“I mean, knocking Michael Jackson from the top of the charts – you would have been a bit crazy to predict that,” Markey says.

“But something was clearly in the air, and we all felt it. It was the first and last time something like this has happened on such a mass-cultural scale. The one pop-culture Beatles moment for me, my friends and peers, and like-minded music fans.

“I have a theory about great records, and it has to do with the first three songs and the way they play together. NWA’s Straight Out Of Compton had the same thing going for it. Those first three songs … damn, they got me, hook, line, and sinker, and I was apparently not alone.

“There have been many great records since, but none of which the whole world agreed on. At least not in the same way. That was the deal with Nevermind, anyone could get to it, and did.”

London-based journalist and author Andrew Mueller, who was working for Melody Maker when Nevermind broke, agrees.

“With Nevermind, Nirvana was a band that a lot people were relieved to find out they liked,” he says. “A lot of people who would have found listening to underground, alternative rock kind of difficult or unpalatable all of as sudden just thought, ‘hey I actually like this. I’m one of the cool kids’.”

Mueller, who often travelled to Seattle in the Nineties to report on its exploding alt-rock music scene, believes no album has come close to Nirvana’s impact since.

And, he says, that’s part of its enduring appeal. “This was one of the last major hits under the old model of the music business, under the old model of popular culture,” Mueller says. “It’s very, very difficult for one band or artist to completely dominate the centre stage like Nirvana did – there’s too much going on. There’s too many other ways of covering it.

“Twenty years ago there was almost no music on TV, there were really only half a dozen music magazines between Britain and America with any influence or power to accomplish anything. If you got into the position where you dominated those, then you really really dominated. And, with Nevermind, Nirvana were absolutely huge in a way that is very difficult for a band to become today.”

British reggae artist Little Roy has just released Battle For Seattle, an album of Nirvana songs covered in a reggae style.

That the album instantly shot to number one on both the iTunes and Amazon charts is testament to the band’s lasting appeal. Roy admits he wasn’t the biggest Nirvana fan before deconstructing the songs, slowing them and putting an offbeat behind them. However, during the process he realised just how good a songwriter Kurt Cobain was.

“The songs, they have great melodies. You hear them and your ear would perk to them. I’m a fan now. Going inside his music, knowing the lyrics: his songs are commanding,” he says. “They are great fun to play. Some songs, the audience seem to get in a trance when they are singing them.”

That’s a sentiment that Charles R Cross, who wrote Cobain’s biography, Heavier Than Heaven, echoes. He puts Nevermind’s lasting impact down to the quality of the late singer’s lyrics more than anything else.

“Because Cobain’s songs were so full of emotion, suddenly it became okay for a songwriter to tackle alienation, divorce, and addiction within the framework of metaphorical lyrics,” he says.

And, he adds, Nevermind also seems to represent the end of an era.

“After 1991, music fractured into so many different genres – there wasn’t just hip hop, but drum and bass, deep bass, trance, and so on – that Nevermind has taken on an even more important place in music.

“It may be the last great rock record that gained mass appeal and critical acclaim. And Cobain, always charismatic, contradictory, and curmudgeonly, might be the last great rock star.” ?