Massive television exposure from the Nelson Mandela birthday extravaganza might have catapulted Tracy Chapman to the top of the albums chart but her initial break came two months earlier, courtesy of one person: Natalie Merchant of 10,000 Maniacs.

That the unknown Chapman could sell out two nights at a London theatre was due entirely to Merchant's impassioned patronage and the lure of seeing Natalie perform a solo set. But, seven years on from their formation, such is the 10,000 Maniacs phenomenon. At the end of this month they headline the prestigious Cambridge Folk Festival, followed by two sold-out London shows. Total adulation is guaranteed, quite something for this self-confessed "goofy-looking bunch" from the rural New York state enclave of Jamestown.

10,000 Maniacs were founded as a six-piece in 1981 by Robert Buck (guitar), Steve Gustafson (bass) and Dennis Drew (keyboards) who then recruited second guitarist John Lombardo, drummer Jerry Augustyniak and 16-year-old singer, Natalie Merchant. Early gigs saw the band relying on covers of songs by a host of artists including Joy Division, Gang Of Four and Talking Heads, and then veering off into reggae, blue grass, country and folk.

Such a bizarre assortment must account for the frustratingly uneven bent of their early records.

The first of these appeared in 1982, the five-track EP Human Conflict Number Five, followed the year after by the album Secrets Of The I Ching.

Both were originally US only releases on the band's own Christian Burial label but were subsequently released in Britain by Press/Compendium International Records in 1984. Both records, now devilishly difficult to get hold of, were blurred in their realisation, vaguely hinting at brilliance but only occasionally coming close. Tension and Planned Obsolescence stand out from the EP, brittle, melodic pop that was striking in its ineffable otherworldliness. Most curious of all was Natalie Merchant's quavering voice, rich in emotion and expression. But precisely what she was emoting and expressing was far from obvious, so strange was her diction; the opening line to My Mother The War from the I Ching album - "she borders the pavement" - still sounds like - "She buys a Big Mac"!

The l Ching album gave further glimpses of a truly remarkable music and still refrained from revealing all. Tension and The Latin One were exhumed from the EP [note this is not correct - The Latin One did not appear on Human Conflict #5. ], the latter being Wilfred Owen's poem Dulce Et Decorum Est set to a loping reggae beat.

The futility of war, as crystallised in Owen's words, was obviously a theme close to Merchant's heart. Grey Victory recalled the destruction of Hiroshima: "Instantly one thousand flames arising/ill scent the burning hides surrounding/a settlement debased entirely/Enola Gay had made a casual delivery".

The album ended with My Mother The War, the only track on these early releases to muster the cohesive power of what was to come. Fulfilling his familiar patron of the arts role, John Peel plugged this startling song relentlessly and, at the end of 1983, 10,000 Maniacs found themselves nestling loftily in that most singular barometer of taste, the Festive Fifty.

Yet 10,000 Maniacs remained something of an enigma until the 1985 release of their first album for Elektra, The Wishing Chair. It was a colossal step forward, recorded in London with Joe Boyd who that year also produced REM, close friends and spiritual allies of the Maniacs.

Blessed with the major label benefits of time and money, The Wishing Chair was the most clearly defined 10,000 Maniacs thus far, with an obvious intent to pare down the multifarious style-mongering of the first two releases which had at times smacked of willful eclecticism.

The folkish hues were more strongly etched, perhaps not surprising with Boyd at the controls, but there was, as always, a distinctive pop sensibility about the band that belied the lazy categorisation on which too many journalists were content to rely. Scorpio Rising, for instance, reveled in a proto-metallic fury, conspicuously short of "Hey nonnies", while a re-recorded My Mother The War proved that the original's searing violence could actually be surpassed. Never shy to update oldies, the Maniacs brought back Grey Victory and Tension made its third appearance, albeit cunningly disguised as Tension Makes A Tangle.

But their talent was still too thinly spread over the course of an album. Little indulgences were not curbed, half-cocked ideas passed off as songs, and the truly great record continued to elude them.

In July 1986, John Lombardo quit the band. Always the most experienced musician, his departure seemed to galvanize the remaining five Maniacs into concentrating their energies and honing the scope of their music.

The evidence of this lies in the glorious form of last Autumn's In My Tribe, a quite dazzling album of richly textured guitar pop. Suddenly, 10,000 Maniacs sounded assured and aware of their considerable capabilities, a new found confidence tangible from the opening bars of What's The Matter Here? on.

The band chose Peter Asher to produce the record (previous credits included Linda Ronstadt and James Taylor) and the results were powerful and lush, but never bland.

A crucial development was the sudden clarity in Natalie Merchant's vocals, a step away from her former preoccupation with "pure vowels and consonants". There could be no doubt as to the meaning of Gun Shy, written when she learned of her younger brother's decision to join the army, or Cherry Tree, relating the plight of the illiterate. Even a Cat Stevens song, Peace Train, was rendered bearable - amazing.