Judas Priest released their fifth album in October 1978. But what it was called depends on where you live.

In the U.S., the LP was titled Hell Bent for Leather, a fitting choice given the band’s newly acquired leather-and-studs image. But almost everywhere else the album was known by its original title: Killing Machine. In a curious move, the States chose sex over violence -- a rarity in the U.S. marketplace.

But the music on Priest’s fifth release was the same, and it firmly announced to fans that the British metal champions were finding new ways to both streamline and modernize their sound by dispensing with most of the lumbering tempos, protracted song lengths and unnecessary complexities typical of the proto-metal and prog rock found on their earlier records.

Songs like "Delivering the Goods," "Rock Forever," "Hell Bent for Leather" and "Running Wild" are short, fiery and to the point. Perhaps inspired, in part at least, by punk's relative simplicity, the tracks retain the undiluted metallic power and sheer sonic weight of the group's earlier cuts, but bolster the overall pace, energy, and melody -- ultimately expanding their commercial appeal.

Once Priest perfected their new musical and visual direction, initially on tour (documented on 1979’s Unleashed in the East) and then on the 1980 follow-up album British Steel, heavy metal was ready to be embraced by mainstream radio, paving the way for its rise toward global domination throughout the '80s.

And some of that progression (not to mention the steep spike in leather jacket sales) can be traced back to the confusingly twin-titled album Judas Priest released in 1978. No matter what you call it, Killing Machine / Hell Bent for Leather was a pivotal record in the band's career and, eventually, the history of metal.

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This Day in Rock History: October 9

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