Deep Purple consolidated their standing as one of the planet's fastest rising hard rock propositions with the July 1971 release of Fireball. The album followed the previous year's watershed In Rock in redefining the group's heavier musical direction, to great commercial success.

Prior to these two, now widely deemed classic albums, a slightly different lineup of Deep Purple featuring guitarist Ritchie Blackmore, organist Jon Lord, drummer Ian Paice, vocalist Rod Evans and bassist Nick Simper had already recorded all of three late-'60s LPs that were marked by inconsistent songcraft and quite a bit of experimenting, The departure of Evans and Simper (replaced by Ian Gillan and Roger Glover, respectively) fixed the songwriting issues on In Rock, and latter quality made something of a comeback on the quintet's fifth album.

Fireball’s eclecticism may boil down to its lengthy recording process over nine months, with frequent interruptions for lucrative touring runs, as Deep Purple’s star rose like a comet. Sessions first began in September 1970, but the only track completed was the very funny “Anyone’s Daughter,” which was inspired both by Blackmore’s favorite country music pickers and the Ten Years After guitar god Alvin Lee.

Then, following a series of commitments that took them to Germany, Scotland and elsewhere, the band reconvened in London long enough to complete one more song, the catchy “Strange Kind of Woman,” which was promptly released as a single (backed with "I’m Alone”) in February and rose to No. 8 in the U.K. charts, whetting appetites for a new Purple album which, as only those close to the band knew, was nowhere near finished.

But thankfully, after a 19-date British tour, an eight-day odyssey to Australia and a quick trip to Iceland, Deep Purple's management finally carved out some studio time for the band to finish Fireball. Their main motivation for finishing was that they were getting increased pressure from Purple’s U.S. label, Warner Bros., which was demanding a new album ahead of Purple's already booked July American tour.

Out of these final sessions in the spring of 1971 came the album's irrepressible title track (its opening swoosh obtained, according to Gillan’s autobiography, from the studio’s heating system), the rather repetitive but effective "No No No" and the hypnotic "Demon's Eye," which replaced "Strange Kind of Woman" on the album's British pressing.

Other new songs completed for Fireball's second side were "The Mule" (a popular instrumental, later stretched to epic lengths on stage), the musically and lyrically venomous (if slightly overlong) "Fools," and an absolute scorcher in the LP-closing “No One Came," which, as Gillan described in his bio, reflected his lingering insecurity about the band’s meteoric rise and, he feared, potential fall.

Alas, the singer's worries proved totally unfounded in the short run, as Fireball climbed to an impressive No. 32 in America (no doubt aided by the band supporting Rod Stewart and the Faces on the road) and then, when it as was finally released in Europe that September, shooting all the way to No. 1 in the U.K., Germany, Sweden, Denmark and Belgium, and reaching the Top 10 in many other countries.

Deep Purple would of course achieve even greater heights of global success with the following year's Machine Head. This pattern of unrelenting touring and rushed recording timelines would put a strain on the musicians and their relations with dire consequences a few years down the line. But in 1971, Deep Purple were as hot as a Fireball.

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