Metal, born from the British blues scene and the darker side of psychedelia, arrived in the late 1960s a heady mix of influences and not yet clearly defined. Although by no means the only exponents of the genre, the emerging sound was spearheaded by Black Sabbath, Led Zeppelin and Deep Purple.

Led Zeppelin was the first of these bands to receive coverage in the Observer, with Tony Palmer’s enthusiastic enthusiastic 1969 review of this ‘worthy successor to the defunct Cream’ who display a ‘fearful tension... a totality of sound’ and ‘barbaric splendour’ on their debut LP. Palmer noted the sensation the band were causing in the United States, with advance album orders of 50,000. ‘Now the group is coming to England where they can be assured of a certain fashionable success.’

Deep Purple also received attention from the paper, due in no small part to keyboardist Jon Lord’s classical leanings, which resulted in a performance with the Royal Philharmonic Orchestra at the Albert Hall. The Guardian’s classical reviewer Meirion Bowen appreciated the band’s musicianship but was perhaps not entirely convinced by this fusion of genres.

Deep Purple’s triumphant show at 1974’s California Jam was covered by Lee Langley and holds the honour of the first mention of the term ‘heavy metal’ in the Guardian: ‘The lights blaze, the vast speakers tremble and boom: Deep Purple is a heavy metal group: hard driving rock. Excitement. You can feel the beat thumping inside your rib cage, taking over your body, battering your ear drums, possessing you.’

Black Sabbath, usually credited as the first proper metal band due to their doom-laden sound and image, were praised in a 1973 piece reviewing the Alexandra Palace Festival. ‘Black Sabbath are heavy. By which I mean they put out a monstrous and implacable wall of noise... and when they imagine their guitars are sabres rather than battering rams they are very good indeed.’ Such praise was a rarity for metal in these early years, when established critics such as Lester Bangs famously decried Sabbath as ‘just like Cream! But worse.’

As the 70s progressed metal lost its hold on mainstream audiences, as rock music fractured between the extremes of polished AOR and the DIY ethos of punk. The Guardian’s Mary Harron was therefore slightly surprised in 1980 to find a burgeoning metal scene in Sheffield centred at the Wappentake pub. Metal ‘never died... a handful of groups kept playing to their loyal followers... they clung tenaciously to their old music.’

Local headbangers, as the fans now called themselves, came to the pub to hear the DJ spin the newest Iron Maiden, Judas Priest and Saxon records, part of the New Wave of British heavy metal who played with ‘more vitality than the old wave’. Opinion however had turned against local success story Def Leppard; as one ex-fan put it: ‘They’ve sold out. Well they’ve gone to America haven’t they?’ Metal’s enduring popularity out of the spotlight was to Harron ‘a phenomenon’. Or as put by a teenage fan, ‘People like us, we’ll never die out.’

By the early 1980s the Guardian had started carrying a handful of reviews of metal gigs as the genre again grew in popularity. Mötorhead got a positive write-up in 1982 for their lack of pretension and ‘honest mania’, while in 1984 Iron Maiden were noted for the ‘arresting visual spectacle’ and the way that at the end of a song ‘the guitarists go wilder and wilder, prefiguring the audience’s cue to lose control’.

The Guardian also ran a feature when the excesses of the genre were (lovingly) mocked in the now cult film This is Spinal Tap.

By the mid 80s metal had spawned an increasing number of sub-genres. The most popular was glam metal, typified by LA’s Mötley Crue, who received a damning review in the paper: ‘Mötley Crue’s songs have the ring of being hastily conceived in the moments between discussing endowment mortgages and pension schemes with business managers.’

By 1987 something new was coming to the forefront, as fans grew tired of glam metal’s posturing and an industry churning out Mötley Crue clones. American thrash bands influenced by ‘the gloomy legacy of Black Sabbath... the speedier outings of early Deep Purple [and] hardcore punk’ were breaking through, after years building a huge underground following. Mark Cooper in the Guardian, recognised that ‘the likes of Metallica and Anthrax... is about to find itself in a conundrum, coping with mainstream success born from a noise designed to outrage’.

Metallica’s answer was of course the Black Album: out went thrash metal and the complexity of 1988’s multimillion selling ...And Justice For All, and in came huge songs destined for stadium singalongs, most famously Enter Sandman and the confessional ballad Nothing Else Matters.

Adam Sweeting questioned whether Metallica had left metal behind altogether – Thrash to Riches: Have the razor boys who recorded Kill ‘Em All gone soft? The album topped charts across the world, including the UK, going multi-platinum in many countries. Metallica drew in new fans who had never before owned a metal album.

Whilst unlikely to be a diehard fan’s favourite Metallica record – that honour usually goes to early albums Ride the Lightning or Master of Puppets – The Black Album holds an important place in metal’s history as a moment when heavier music once again stormed the charts.