Steve Harley was many things, but a man held back by modesty was not among them.

In his first big music press interview – before the appearance of Cockney Rebel’s debut album, when all they had released was a solitary single that featured a 40-piece orchestra, which had failed to make the UK charts – he proclaimed his band “a musical force that others will follow” and pitted himself squarely against the biggest names in British pop. Cockney Rebel, he suggested, would kick David Bowie “up the arse”: “he’ll say ‘I’ve got to step on it to stay at the top’.”

When it arrived, Cockney Rebel’s debut album featured a song called Mirror Freak that loudly announced he was going to supplant Marc Bolan – “too cute to be a big rock star” – in the public’s affections: “We can feel a change is on the way … a new man he appears to be winning … you’re the same old thing we’ve always known.”

Harley was given to dismissing any band that had a lead guitarist, a musician noticeably absent from Cockney Rebel’s line-up and on another occasion, he claimed the band were so good that divine intervention had to be involved: “I feel like God’s touched me and said ‘here’s a mission and someone’s gotta do it’.”

This was big talk that perhaps told you something about Harley’s background as a journalist: he may have only worked for local papers, but he knew what made for lively copy. The thing was, that for a moment at least, Harley appeared to have the goods to back up his more extravagant pronouncements.

Cockney Rebel’s first two albums, The Human Menagerie and The Psychomodo, arrived alongside the first signs that glam rock was waning, or at least that its most artful practitioners were moving on – Bowie had killed off Ziggy Stardust, Bolan had announced the genre “dead” and “embarrassing” – and suggested the arrival of a fresh take.

Whatever you made of Harley’s thoughts on electric guitars, their relative, if not complete, absence from Cockney Rebel’s sound gave them a clear point of difference. Driven instead by electric piano and Jean-Paul Crocker’s electric violin, you could definitely make out the influence of Bowie and the kind of 50s rock’n’roll that was a touchstone throughout glam, but their sound also drew on psychedelia, Brecht and Weill cabaret, folk (Harley had done time in Britain’s folk clubs and as an acoustic guitar-toting busker) and, occasionally, classical music.

His voice was a mannered sneer that occasionally sounded a little like The Kinks’ Ray Davies and occasionally seemed to presage the arrival of punk – it was certainly the perfect fit for his lyrics, which were both thick with lurid imagery – “hooked on absinthe and daffodils/telling tales of white gardenia” – and big on withering disdain.

If the lyrics could occasionally seem a bit florid for their own good, Harley was clearly an impressively gifted songwriter: listen to the flatly brilliant Ritz, from The Psychomodo, The Human Menagerie’s shimmering Hideaway or Tumbling Down. He was willing to take musical risks – The Human Menagerie’s closer, Death Trip, stretched out over 10 episodic minutes; perhaps the reason their debut single, Sebastian, flopped in the UK was because its high-drama orchestration was completely at odds with everything else in the British chart – and apparently capable of writing hits to order.

Stung by the failure of Sebastian and The Human Menagerie’s slow sales, he knocked out Judy Teen, infernally catchy, decorated with backing vocals that seemed to nod in the direction of Lou Reed’s Satellite of Love and the song that effectively propelled Cockney Rebel from music press bete noir to mainstream fame.

But almost as soon the original Cockney Rebel attained success, they collapsed: arguments over money, apparently exacerbated by Harley’s grandstanding insistence the band stay in the most expensive hotels while on tour, led every member except drummer Stuart Elliott to mutiny. Harley fulminated about their disloyalty in the music press, and released a flop single Big Big Deal – better than its cool commercial reception suggested – before having the last laugh in quite spectacular style, pouring his bitterness and resentment into a perfect pop single: Make Me Smile (Come Up and See Me), which masked the spite of its lyrics with an utterly irresistible melody and arrangement, and rocketed to No 1.

An exceptionally well-crafted set of songs, recorded with a team of crack session musicians, the subsequent album Best Years of Our Lives was the biggest hit of Harley’s career. The two albums he released in 1976, Timeless Flight and Love’s A Prima Donna, also had their moments – the dreamy Understand on the former, the title track and (Love) Compared With You on the latter – but trouble was brewing. Unlike Bowie, Bolan or Roxy Music, Harley was not among those glam-era stars whose name remained hip to drop during punk (although Andy Partridge of XTC was apparently a fan, as was evident from his early vocal style) and he struggled to find a place in the new musical landscape: matters weren’t helped much by 1978’s Hobo With a Grin, an ill-judged attempt to sand down his idiosyncrasies and make an album appealing to the mainstream US rock market – he subsequently disowned it as “the worst thing I’ve ever done”.

The following year’s The Candidate was a marked improvement, the distorted guitars and synthesizer of Freedom’s Prisoner retooled the sound of Cockney Rebel’s 1974 single Mr Soft for the new wave era, and it was promoted by Harley in typical style: “I’m back and they’re all going to know I am.” It failed to make the charts and resulted in Harley being dropped by EMI. It was the last album he released for 13 years.

Although he occasionally released singles, and made an unexpected return to the Top 10 duetting with Sarah Brightman on the title song of Andrew Lloyd Webber’s The Phantom of the Opera, he largely concentrated on raising his children, a sabbatical presumably bolstered by the fact that in Make Me Smile (Come Up and See Me), he’d written the kind of song that means there’s no great financial imperative for its author to work. By Harley’s own estimation, it had been covered more than 120 times, most notably by Duran Duran at the peak of their 1980s fame. It has appeared in umpteen movie soundtracks and in adverts for everything from Viagra to Marks & Spencer, and remains one of the most-played songs in British broadcasting history.

He returned in the 1990s with a sporadic succession of albums. He cheerfully admitted that most people only knew him for Make Me Smile (Come Up And See Me) – “I realise half the world and its grandmother think I wrote just that song” – and indeed, there’s a sense that Cockney Rebel’s early albums have never quite been afforded the kind of attention they deserve. And sometimes, even in his later years, he was quite capable of summoning up the bullish Steve Harley of old, snapping at interviewers who suggested Cockney Rebel had been influenced by Bowie or Mott the Hoople (“I wouldn’t credit either of them”) or still sounding chuffed about putting one over the bandmates who left him in 1974: “It must have been difficult,” he told the Guardian, with a distinct hint of relish, “watching me singing that song on Top of the Pops”.

Still, as he pointed out, he had earned the right to be self-aggrandising. If he had never actually delivered David Bowie the “kick up the arse” he once promised to, he had made a striking contribution to 1970s rock – The Psychomodo in particular remains a masterpiece of wilfully OTT decadence: 50 years on, it still sounds unique. “Ritz, Tumbling Down, Cavaliers,” he remarked, listing said album’s highlights. “I’d like to go to my grave believing no one in the world could have written those songs but me. No bragging there. I hear them and think ‘ah – that’s me’.”

• This article was amended on 18 March 2024. Steve Harley’s 1979 album was called The Candidate not The Prisoner.