Heavy metal music
Critics disagree over who can be thought of as the first heavy metal band. Most credit either Led Zeppelin or Black Sabbath, with American commentators tending to favour Led Zeppelin and British commentators tending to favour Black Sabbath, though many give equal credit to both. A few commentators—mainly American—argue for other groups including Iron Butterfly, Steppenwolf or Blue Cheer. Deep Purple, the third band in what is sometimes considered the "unholy trinity" of heavy metal (Black Sabbath, Led Zeppelin, and Deep Purple), despite being slightly older than Black Sabbath and Led Zeppelin, fluctuated between many rock styles until late 1969 when they took a heavy metal direction.
New wave of British heavy metal
The UK was a cradle of the first wave of heavy metal, which was born at the end of the 1960s and flowered in the early 1970s. Of the many British bands that came to prominence during that period, Led Zeppelin, Black Sabbath and Deep Purple achieved worldwide success and critical acclaim. The success of the music genre, usually called heavy rock at the time, generated a community of UK fans with strong ties to psychedelia, hippie doctrines and biker subculture. Each of these bands was in crisis in the mid-to-late 1970s: Led Zeppelin were plagued by discord and personal tragedies and had drastically reduced their activities, Black Sabbath finally fired their charismatic but unreliable frontman Ozzy Osbourne, and Deep Purple disbanded. As a consequence, the whole movement lost much of its momentum and media interest, which were refocused on what British writer Malc Macmillan calls "the more fashionable or lucrative markets of the day" such as disco, glam, mod revival, new wave and electronic music. Just like progressive rock acts and other mainstream music groups of the 1970s, heavy rock bands were viewed as – in the words of journalist Garry Bushell – "lumbering dinosaurs" by a music press infatuated with punk rock and new wave. Some writers even declared the premature demise of heavy metal altogether.