Music fans who visited record stores in April 1980 likely found themselves confronted with a horrifying creature of leathery skin and spiky hair staring wide-eyed and gape-mouthed at them. This ghoulish character, Eddie, would soon go down in heavy metal lore as a band's ubiquitous and ever-changing mascot. And the band, Iron Maiden, with its self-titled debut album, would also soon go down in metal history.

Though Iron Maiden's rise to stardom today seems like it was inevitable, nothing was guaranteed when the group was founded by bassist Steve Harris on Christmas Day 1975. They spent the rest of the decade paying their dues in order to arrive at their momentous album release at the dawn of the '80s. While they were one of the most wildly hyped bands in the New Wave of British Heavy Metal, nobody had a clue how they would fare with the wider marketplace and whether they would have any sort of career, let along a long and successful one.

Look no further than the staggeringly low success rate of other genre bands. Only Def Leppard came anywhere near to matching Iron Maiden’s popularity, and they had to abandon their original sound to do so. Early favorites such as Saxon, Samson, Diamond Head and Angel Witch faded into cult popularity to varying degrees. Even Iron Maiden -- whose talent, professionalism and sheer drive topped most of their peers' -- faced many challenges along the way, many of which hit them as they prepared to record their crucial first album.

As late as Christmas 1979, Harris and Maiden’s strong-willed manager, Rod Smallwood, were still tinkering with the band’s lineup, dispensing with longtime drummer Doug Sampson (due to health concerns) and recruiting Clive Burr to join singer Paul Di’Anno and guitarists Dave Murray and Dennis Stratton (who landed the job not even six months earlier). They then started searching for a producer to oversee their album, quickly crossing Guy Edwards and Sweet's fundamentally mismatched guitarist Andy Scott off the list, before settling on their label EMI’s next suggestion, Will Malone.

But this arrangement would prove less than ideal once Iron Maiden started tracking songs at London’s Kingsway Studios in January. Though he had worked with Black Sabbath, Todd Rundgren and Meat Loaf in the past, according to sources (including Mick Wall's Run to the Hills: Iron Maiden, the Authorized Biography), Malone was reportedly disinterested and emotionally disengaged throughout the sessions, forcing the band to take charge during recording.

By the time they were forced to wrap up work on Feb. 1, they had joined the Metal for Muthas tour, and then spent the remainder of the month shuttling back and forth to London, as time allowed, to mix the album. But they couldn’t pass up the chance to hop aboard Judas Priest’s British Steel tour, which kicked off on March 7. A month later, Iron Maiden was released and debuted at No. 4 on the British chart.

The album's accidentally raw aesthetic gave songs like “Prowler,” “Charlotte the Harlot,” “Iron Maiden” and especially first single “Running Free” a punk energy, something missing from the rest of the band's work. That same rough-and-tumble approach didn't cast the best light on more dynamic compositions like “Remember Tomorrow,” “Strange World” and the ambitious “Phantom of the Opera,” but Iron Maiden’s natural prowess got them through.

The reception to the LP ignited a historic career for Harris and his routinely changing cast of bandmates as they conquered benchmark after benchmark, achieving glory after glory, over the decades. It certainly helped that legendary producer Martin Birch joined their team the next year and helped craft Killers, a work that wouldn't have been possible with the perfectly flawed first album.

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