Judas Priest undertook a '70s-era rite of passage when they recorded Unleashed in the East – their first, and arguably still-definitive concert document – in February 1979.

Though many of their contemporaries issued two-disc live albums at the time, Unleashed in the East was confined to a single slab of vinyl. With it, Judas Priest not only earned a deserved place among the decade's most acclaimed live LPs but also gave many of their newest fans a chance to become acquainted with the band’s earliest work.

Their first two records, the uneven 1974 debut Rocka Rolla and sophomore doom masterpiece Sad Wings of Destiny, came out before Judas Priest started to gain creative and commercial momentum via Columbia Records-backed heavy-metal building blocks like Sin After Sin, Stained Class and Hell Bent for Leather.

Each of these studio LPs was supported by grueling but rewarding tours, stretching ever further across the U.K., U.S. and Europe, until they brought Judas Priest to Japan in the fall of 1978. They returned in 1979 for the dates that would make up Unleashed in the East.

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Released in Japan as Priest in the East, where it featured four bonus tracks, these recordings included thrilling early speed-metal templates like "Exciter" and "Running Wild" (which forecasted the imminent New Wave of British Heavy Metal), reinvigorated romps through early career warhorses such as the serpentine "Sinner," the morbid "Genocide" and their signature anthem "Victim of Changes."

The band’s covers – Fleetwood Mac’s "Green Manalishi" and Joan Baez’s "Diamonds and Rust" – were wisely chosen and reminded fans of the Judas Priest’s eclectic influences.

There was plenty of studio tinkering after the fact, ranging from the odd overdub to a wholesale re-recording of Rob Halford’s vocals – which were unusable in the original concert tapes. That, too, was in keeping with the times, as classic live albums like UFO’s Strangers in the Night and Thin Lizzy’s Live and Dangerous were also subjected to significant sonic overhauls before hitting record store shelves.

No matter. Unleashed in the East arrived on Sept. 17, 1979 as a crucial dividing line, demarcating the metal gods’ inexorable rise to relevance throughout the late ‘70s to their world-dominating triumphs in the ‘80s and beyond.

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