Watch: Oasis share demo version of ‘Sad Song’ with Liam on vocals

Their second album may have become the UK's third biggest-selling studio long-player of all time, but with every passing year this debut becomes more established as an unassailable career zenith. Often plausibly compared with Never Mind The Bollocks, Here's The Sex Pistols, this album's cultural impact was in some ways as far-reaching (if not politically), as it reignited British rock. It also took endless tinkering mix-wise to finesse Noel's beefed-up guitars, but there was a purity and purpose to his songs on Definitely Maybe that can never be repeated. From Live Forever's gutter-level stargazing and Slide Away's desperation to Rock'N'Roll Star's magical self-fulfilling prophecy, it simply cannot be bettered.

Though the final two Oasis LPs had their moments, such as ultimate piledriver The Shock Of The Lightning off '08's Dig Out Your Soul, this fifth studio outing was the last consistently thrilling one. Having booted out all three of Liam's original bandmates from The Rain and supplanted them with hand-picked indie-rock pros, for Heathen Chemistry, Noel opened the door to others writing songs. Gem Archer's Hung In A Bad Place and, particularly, Liam's Songbird – a breezy love letter to his then fiancée Nicole Appleton – brought fresh energy, while Noel's perennial England-out-of-the-World Cup weepie Stop Crying Your Heart Out topped off a promising new blend that never quite matured.

On release of his second solo record, Noel recalled how he and Gem Archer would reflect on critiques of late-Oasis stodginess, wondering, "What do they expect – space-jazz?" This, clearly, was to prepare the troops for Chasing Yesterday's expansion on solo Noel's first freedoms, to include sax solos (hear blissful, West Coast-ish opener Riverman) and two revised outtakes from a shelved collaboration with cosmic '90s dance troupe Amorphous Androgynous. Themes of middle-aged ravers regaining the old magic, and an appearance by Johnny Marr on wonderfully dreamy disco-pumping closer Ballad Of The Mighty I, sealed another chart-topping victory.

The sixteenth-fastest-selling album in UK chart history got a universal kicking at the time of its release, as critics perhaps detected, of all things, a crisis of confidence in Oasis's leader over creative direction, after the "cocaine expansionist" lunacy of 1997's Be Here Now. Despite side two's Noel-sung missteps, the lumpy Gas Panic! and Little James's cheesy new-father lyrics, the rest of Standing On The Shoulder Of Giants has weathered much better than later records. Opening breakbeat instrumental Fuckin' In The Bushes is a pulse-quickening Zeppelin-esque monster, while the hazy-lazy Go Let It Out offered a superb, acoustic-rattling response to the hot post-Britpop sound of The Beta Band.

Even while Beady Eye was failing commercially, it was Noel who advised, with a winner's smirking disinterest, that his younger brother should go solo, with "his name in lights" – an obvious reference to late-'60s Elvis. The parallel wouldn't be irrelevant when Liam ultimately did so two years later. With the push of a major label behind him, a raft of elite-class songwriters helped sculpt material that essentially celebrated Liamness. Thus, while Noel's solo records sought routes away from Oasis-style rabble-rousing, As You Were simply gloried in it (Wall Of Glass; Greedy Soul), while also, on For What It's Worth, mining the singer's troubled private life with winning vulnerability.

Even on first listen, Noel's solo debut felt like a liberation. Swapping Oasis's stampede of multitracked guitars for a strummed acoustic, and his strained bark for a more natural, choirboy-esque vocal purity, …High Flying Birds birthed a sound that played to his own strengths (thoughtful, sophisticated), rather than Liam's (headlong). Everybody's On The Run and If I Had A Gun…saw him take his foot off the gas to wonder at the world, while proven pop smarts resurfaced in Kinksian whimsy (Dream On) and piano-house-like euphoria (AKA…What A Life!). Britpop's songwriting master had got his edge back.

Following Oasis's split, it spoke volumes that, within weeks, Liam had announced a new band alongside the other three members (guitarist Gem Archer, bassist Andy Bell and final-tour drummer Chris Sharrock), leaving the increasingly isolated 'Chief' Noel to go it alone. By the time Different Gear… emerged, its sense of 'continuity Oasis' felt mistimed – quite simply, the world wasn't ready to welcome Oasis back yet, in any guise. Beady Eye's debut is, however, something of a lost classic, delivering flagrant Lennonisms (The Roller), Who-esque thrills (titled Beatles And Stones, oddly), and piano-trashing rock'n'roll (Bring The Light) with a vitality that bespoke years of repression under the old regime.

A central plank to Oasis's mid-'90s dominance dictated that Noel's songbook was so stuffed with classics, the extra tracks on singles packed more chart-topping potential than any other band's A-sides. Here, as a stopgap after their 1996 Knebworth mega-gig and Be Here Now, they reinforced the point: The Masterplan trounces all later Oasis LPs, too. Three cuts – opening brotherly-solidarity duet Acquiesce, bittersweet soul-searcher Half The World Away, and the orchestral title track – really were Number 1s that slipped the net. Others, like acoustic tearjerker Talk Tonight, clearly weren't, but their variety of mood and instrumentation make a fine companion to the Oasis-in-overdrive 'proper' LPs.

Following his team-up with The Chemical Brothers on '96's Setting Sun, Noel had experimented with 'going dance' in Oasis circa '03-04 via abortive sessions with Death In Vegas, then solo with Amorphous Androgynous. He doubtless felt pressure to modernise, and things eased in that direction with 2017's team-up with Belfast producer/movie soundtracker David Holmes. WBTM upheld solo Noel's sense of casting off shackles, echoing New Order, Phil Spector and The Prodigy, and, in Holy Mountain's use of the glam-y horn riff from Bryan Ferry's Let's Stick Together, reconnecting with early Oasis' 'genius steals' mentality.

It's hard to overplay the breathless, pre-social media phenomenon of Oasis through 1994-95, and how their ascent was mirrored in their second LP's expansion on the debut's raw materials. Most importantly, in Wonderwall Morning Glory had the heartstring-tugging megahit to facilitate the band's crossover worldwide. At every turn there was growth, from Noel's primetime vocal debut on the anthemic Don't Look Back In Anger, to Champagne Supernova's Quadrophenia-on-steroids finale. Quite how much was 'held back' for LP2 by career mastermind Noel is still questionable, but these mighty choruses would soon resound around Earls Court, Maine Road and beyond.

Their second album may have become the UK's third biggest-selling studio long-player of all time, but with every passing year this debut becomes more established as an unassailable career zenith. Often plausibly compared with Never Mind The Bollocks, Here's The Sex Pistols, this album's cultural impact was in some ways as far-reaching (if not politically), as it reignited British rock. It also took endless tinkering mix-wise to finesse Noel's beefed-up guitars, but there was a purity and purpose to his songs on Definitely Maybe that can never be repeated. From Live Forever's gutter-level stargazing and Slide Away's desperation to Rock'N'Roll Star's magical self-fulfilling prophecy, it simply cannot be bettered.