When Liam Gallagher took to Twitter last month, cryptically posting the letters O, A, S, I and S in successive tweets, the cyberspace rumour mill went into overdrive. With talk of an Oasis reunion ever since the band's acrimonious split in 2009, now seemed as good a time as any for it to actually happen. It would be fair to say Gallagher junior's Beady Eye haven't exactly set the rock and roll world alight, while older sibling Noel and his High Flying Birds project may have fared better, but his live shows still rely heavily on material from the Oasis back catalogue. Add the fact Saturday night's prestigious headline slot at Glastonbury was announced at this point and those rumours might bear some credence after all. To cap it all off, this year also marks the twentieth anniversary of Definitely Maybe, the band's first long player and arguably one of the greatest debut albums of all time.

Forget the legacy of awful bands that carved a career in Oasis's wake. Likewise ignore the naysayers that claim Oasis were a spent force from the moment 1997's Be Here Now signified the end of Britpop. They're wrong, as both 2002's Heathen Chemistry and its successor Don't Believe The Truth are fine records worthy of addition to the Oasis canon. Indeed, while Britpop is currently dominating broadsheet arts sections and every social commentator on the web adds their tuppence worth, it's worth reminding ourselves how barren the mainstream British musical landscape had become prior to Oasis' arrival.

The guitar-led indie and Madchester scenes of the late Eighties and early Nineties had petered out, grunge having taken its place both in underground and mainstream circles. While a lot of great music came out of that movement, twice as many imitators scored record deals along the way. Remember Stiltskin anyone? Music had become stale, with many seeking inspiration from the past to create their own slice of history in the future (step forward Blur and Suede).

My first dalliance with Oasis came about thanks to a penpal I used to swap mixtapes with as a teenager. It was early 1994 and a package arrived on the doormat. Squeezed in between artists like Back To The Planet and Sunshot was a song entitled 'Rock'n'Roll Star' by a band I'd never heard before. Even on a C90 it sounded huge and reaffirming. A month or so later that band would play a tiny venue in Derby called The Wherehouse. Along with the other fifty-odd souls present that night I was hooked. Ironically, local grunge poppers Cable supported and while they would also later go on and make positive inroads of their own, it was clearly a case of out with the old sound and in with the new when Oasis followed them on stage.

From the moment 'Supersonic' gatecrashed the Top 40 singles chart that summer, it was clear a sea change was on the way. Two more 45s and four months later, Definitely Maybe lived up to that early promise and some. Even then, rightly considered a landmark album. That it became the fastest selling debut of all time suggested an excitement-starved record buying public had finally found what it had been craving these past few years. The backslapping self-indulgent 'Digsy's Dinner' aside, there was enough spread across Definitely Maybe's 11 tracks (12 if you owned the first vinyl pressing) to suggest this generation's answer to the Beatles or the Stones or the Pistols or the Smiths were unfolding before our very eyes.

And so, 20 years on from its initial release, Definitely Maybe still stands proudly as a pivotal moment for its creators. Follow-up (What's The Story) Morning Glory may have elevated them to stratospheric heights previously unseen for a UK indie band (not to mention the band's then-label, Creation Records) but the foundations were laid by its predecessor 14 months earlier. Recorded between February and April 1994 with Owen Morris at Sawmills studio after initial sessions with Dave Batchelor in Wales had proved expensive and fruitless. Even then, both band and label were initially unsatisfied with the results - only a lack of funds forcing them to either release what they had or scrap the album entirely.

Thankfully they chose the former. Here on the twentieth anniversary deluxe edition, the album gets a complete remastering which does little to enhance or diminish the spirit of the original. The two bonus discs collect numerous b-sides, extra tracks such as the original white label 12-inch version of 'Columbia' and demo of 'Cigarettes & Alcohol' which first appeared on a free cassette given with the NME, unreleased demos including the previously unheard outside of bootleg-land 'Strange Thing' and live recordings.

What's most apparent is the band's development, from the indie-by-numbers likes of 'Fade Away' and 'Strange Thing' through to the first recording of 'Columbia' at Eden Studios then onto the two which subsequently followed it. Liam Gallagher's vocal perhaps weren't quite as snarlingly assured initially, but his trademark pronunciations in place by the time the album hit the shelves. Elsewhere, Noel Gallagher's acoustic renditions of 'Whatever' b-side and 'Royle Family' theme tune 'Half A World Away' have an endearing quality about it, probably due to do them being recorded in a Tokyo hotel room during some extended downtime while on tour. The live recordings of 'Supersonic' and 'I Am the Walrus', both taken from different shows in Glasgow in April and June 1994 also capture the band at their unflinchingly uber-confident best.

At times though, Definitely Maybe: Chasing The Sun suffers from unnecessary overload, and by the end of the third disc with its numerous acoustic renditions of album standards bookended by a pointless instrumental of 'Whatever' one could be forgiven for asking the question how many different versions of 'Up In the Sky' does this package warrant? Nevertheless, for latecomers to the party, this serves as a perfect introduction to Oasis and despite Liam Gallagher's protestations for fans to boycott its release, Definitely Maybe: Chasing the Sun provides a timely reminder why he and his former band are still held with such high regard.