Michael Eavis likes to drop hints that the time is fast approaching when he might pull the plug. Dairy farmer by trade, music promoter by passion, he has kept the faith since 1970 when he decided to mount a music festival – on his Somerset farm! – and call it the Pilton Pop, Blues & Folk Festival. The Kinks were scheduled to headline, but in the end T.Rex served up their full-cream psychedelic folk rock instead. Tickets cost a quid. And the future? Who in 1970 was interested in that? Living the intense present was enough. Follow-up festivals were haphazardly made to happen, until the Glastonbury Festival we know today properly became a fixture in 1981.

Eavis is clearly a man of integrity and discernment. With tin-eared schemers like Simon Cowell wielding pop power out of all proportion to their pop taste, pop as creative going concern is being killed stone dead. Death by puerile, simpleminded ITV Saturday night television is a slow, agonising, stupid way to die; better to bow out now on a high rather than, in 10 years time, risk a pitiful sight like Macca telling anyone who’ll listen ‘I used to be in The Beatles you know’ as his hearing aid trips a feedback loop over the Glastonbury sound system. But, if Eavis did arrive one day at the regrettable conclusion that enough was enough and slammed his farm gate shut, 40 years of rock and pop folklore wouldn’t be the only memory to fade away – music festivals at Glastonbury have a longer and proud and easily overlooked forgotten history.

Today the composer Rutland Boughton is a footnote, Radio 3 afternoon concert fodder if you’re lucky. Truth is, put his bucolic wholesomeness next to contemporaries like Frank Bridge, Gustav Holst and Ralph Vaughan Williams and his scores can’t hack it. Which doesn’t mean Boughton isn’t of interest. In the early years of the 20th century he was driven by serious ambition, a composer aiming to carve out an English counterpart for Wagner’s Gesamtkunstwerk. He set out his ideas in a manifesto he called Music Drama of the Future. His operas were to be bigger than opera – music bleeding into imagery and text (Boughton was especially interested in learning from the role of the chorus in Greek drama), which would elevate the form towards what he termed ‘dramas of the spirit’. But he needed his Bayreuth, a place where he could erect his ‘Temple Theatre’, a fancy new building that could serve his creative work while, hopefully, ‘growing out of the municipal life of some civically conscious place’. And if that didn’t pan out, Plan B: ‘a new city shall grow around the theatre’.

For a composer obsessed with myth and the roots of ancient Albion – an Arthurian opera called The Birth of Arthur had been germinating on his desk since 1908 – Glastonbury was a totally alluring prospect. Considered a sacred site where the earth’s electromagnetic energy fields – ley lines – converge, Glastonbury was, and remains, like Stonehenge or Avebury, an irresistible draw for those who believe in healing, the force of primeval energies and communing with the earth. And even if you reckon that’s a load of hippy hot air, the fact Glastonbury attracts people with those beliefs gives it a default energy and alternative identity.

Like Michael Eavis 60 years later, Boughton took the opportunity to create a festival from the ground up. Utopian socialism would eventually shatter his Glastonbury idyll, but for the meantime, politics was an empowering, motivating principle. Boughton’s thinking was earthed in the arts-and-crafts ideals of William Morris; mend and make do; build your own Jerusalem. The notion was to open the arts up to ‘ordinary’ people. And grander than any annual festival, spontaneous performances would spark out of the interactions of a community of workers and creatives living and thinking together. In the event this proved hopelessly idealistic, and Boughton’s attempt at a first Glastonbury Festival in 1913 collapsed when it was revealed he wasn’t actually legally married to the woman he’d been calling his ‘wife’. The local community voiced moral outrage and Team Boughton decamped to Bournemouth where scenes from The Birth of Arthur were performed in a concert version.

But thinking about how, only a year later, Boughton made good on his certainty that Glastonbury was the place, then projecting those thoughts forwards to Eavis, you’re persuaded that Glastonbury must indeed be a uniquely energising environment. Bouncing back from the marriage debacle, chutzpah like other people have mice, Boughton cultivated impressive celebrity endorsement: Edward Elgar, George Bernard Shaw and Thomas Beecham lent varying levels of support. Festivals were to be held during Easter, Whitsun, high summer and Christmas. The Easter 1915 festival featured a performance of Purcell’s Dido and Aeneas, while Boughton’s own music was never too far away; scenes from The Birth of Arthur, his new opera The Immortal Hour and a Nativity opera called Bethlehem were all mounted during 1915.

Which was good news for Boughton, but those plans for a community-embracing festival – how were they working out? This is an issue that, from Aldeburgh in the south to the Huddersfield Contemporary Music Festival in the north, all festivals must eventually face; ought a festival be imposed, however benevolently, upon a community, or should that community somehow be integrated into the day-to-day activities of the festival?

Boughton and Eavis tried to approach their Glastonbury festivals in a spirit of wider social awareness. In 1981, Eavis began organising his festival in partnership with CND (the Campaign for Nuclear Disarmament); in 1914 Boughton instigated a School of Music and Drama, workshops and classes for the locals in dance, singing, instrumental playing and costume design, lessons which fed into the main festival. But both men also found themselves dealing with unexpected problems thrown up by the realpolitik. The modern Glastonbury very nearly got derailed in 1990 when security guards fought to block new-age travellers from scaling the perimeter fence and the festival ended in ugly violence, a spectacle that knocked awkwardly against memories of the festival’s hippy roots. Peace, love and…perimeter fences? Riots? But Eavis’ toughest challenge has been to retain something of the idealism that fired him up all those years ago – an increasingly thankless proposition as audiences now wear the CND logo as a fashion symbol, and pop no longer goes snap and crackle.

And politics was the downfall of Boughton’s Glastonbury. His opera The Immortal Hour proved so popular that it was staged in London in 1922, and again a year later, clocking up an impressive 376 performances. But as an increasingly politicised Boughton staged a London production of Bethlehem in support of the 1926 General Strike, Jesus born in a miner’s cottage and Herod portrayed as a Fat Cat capitalist, the manufactured indignation of a politically unsympathetic press proved unforgiving. When news of the scandal reached Glastonbury, the festival directors buckled under the pressure and steps were taken to close the festival down. It ceased to exist officially in 1927.

Festivals driven by idealism and passion have an annoying habit of becoming successful, popular even, and that’s precisely when that same idealism is put under pressure. Eavis has managed to bend with the wind (and the mud) to maintain a much evolved Glastonbury which, he hopes, retains something of its founding magic. Boughton’s festival is no more, but his Glastonbury arguably drew the template, made the mistakes, set the mood – Aldeburgh and Bath would surely have had a harder time establishing and sustaining themselves without its example. And then there’s The Proms, essentially paid for by the general population and offering that same population a banquet of affordable music. Boughton could only have approved. Just imagine the smile on his composer’s face as this most committed of Wagnerians did the sums: a whole Ring Cycle, Tristan and Isolde, Parsifal and Tannhäuser, standing in the arena in 2013, yours for £35. Now that’s a festival.