Among farmers, actors, musicians, theologians and used car dealers, Greenbelt was born on the unsettled non-conformist edges of the church.

And those who had always had a hunch it might be more interesting on the fringe than at the centre soon found a home in the festival.

' The Sun' billed it 'The Nice People's Pop Festival', but perhaps it was more subversive than it appeared. In the 70s Greenbelt's wholistic take - Bible in one hand and newspaper in the other - had a transforming impact on those attending.

If the initial draw of the Festival lay in its celebration of the arts, particularly rock music, the appeal broadened as a growing internationalism emerged from the festival organisers. Soon Greenbelt gained a reputation for introducing people to the UK church who came from places where the struggle for justice was more pressing than, say, 'the baptism of the Holy Spirit'. Among these voices were Nicaraguan minister Gustavo Parajon, South African anti-apartheid activist Caesar Molebatsi and Elias Chacour, a Palestinian Melkite priest from Galilee.

As the evangelical musical subculture all-but dried up, the heart and mind of Greenbelt broadened and strengthened. Soon, artists were invited not just because they were believers or had distant churchgoing relatives, but because their vision overlapped with a biblical one of global justice (Bob Geldof) or engaging with the political powers (Midnight Oil) or was simply fuelled by a divine sense of wonder (Waterboys).

There were tensions between those who wanted Greenbelt to remain more evangelical and those who wanted it to become more ecumenical, between those who wanted it to be more religious and those who wanted it to be more political, and between those who wanted more music and those who wanted more theatre and visual arts. But, even with these tensions, a sense of wonder and worship permeated the festival. And this feeling of a creative Christian community at worship reassured those who might have been sceptical, for example, about progressive elements in the arts programme.

But not everyone was fooled! As the 80s became the 90s many were alarmed that the festival was sometimes hosting people from other Christian traditions (and none) or that it appeared to be hostage to an increasingly leftist and liberal agenda. When mistakes were made - as they often were - critics would pounce. Greenbelt had 'left its moorings' was the grapevine gossip. Sometimes other 'gatekeepers' were worried at the direction: youth leaders weren't sure about the laid-back, chilled-out, opt-in approach of Greenbelt - epitomised in the Rolling Magazine - which contrasted with the focussed bible-teaching of other events. For some, it seemed, Greenbelt was just not serious enough.

Festival numbers declined in the 90s. And a series of disastrously wet August Bank Holidays didn't help. Only the loyalty of a core of committed believers who'd grown up with the festival kept an increasingly unlikely show on the road. And it was these Angels who helped Greenbelt make the transition from its evangelical origins to a more broad-based partnership with a range of mainstream church organisations. With their monthly contributions, Greenbelt was able to invest in itself again and numbers have nearly quadrupled in the last four years.

As the festival has cemented its partnership with development agency Christian Aid, Greenbelters have been able to translate debate about political engagement and international injustice into vigorous campaigning. Other organisations have also entered into collaboration - from CMS and SPCK, to USPG and YMCA, ICC and The Church Times. Enhancing the festival's identity, they have also helped Greenbelters re-imagine the church as an infectious global conspiracy, working for God's peace, healing and friendship in previously unimagined ways.

And that was just the first thirty....

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