The UK charts were inundated with glam rock acts from 1971 to 1975, with glam also manifesting in all areas of British popular culture during this period. The March 1971 appearance of T. Rex frontman Marc Bolan on the BBC's music show Top of the Pops, wearing glitter and satins, is often cited as the beginning of the movement. Other British glam rock artists include David Bowie, Freddie Mercury of Queen, Mott the Hoople, Sweet, Slade, Mud, Roxy Music and Gary Glitter. In the US the scene was much less prevalent, with Alice Cooper and Lou Reed the only American artists to score a hit. Other US glam artists include New York Dolls, Iggy Pop and Jobriath. It declined after the mid-1970s, but influenced other musical genres including punk rock, glam metal, New Romantic, and gothic rock and has sporadically revived since the 1990s.
Glam rock can be seen as a fashion as well as musical subgenre. Glam artists rejected the revolutionary rhetoric of the late 1960s rock scene, instead glorifying decadence, superficiality, and the simple structures of earlier pop music. Musically it was very diverse, varying between the simple rock and roll revivalism of figures like Alvin Stardust to the complex art rock of Roxy Music. Artists drew on such musical influences as bubblegum pop, the brash guitar riffs of hard rock, stomping rhythms, and '50s rock 'n roll, filtering them through the recording innovations of the late 1960s.
Visually it was a mesh of various styles, ranging from 1930s Hollywood glamour, through 1950s pin-up sex appeal, pre-war cabaret theatrics, Victorian literary and symbolist styles, science fiction, to ancient and occult mysticism and mythology; manifesting itself in outrageous clothes, makeup, hairstyles, and platform-soled boots. Glam is most noted for its sexual and gender ambiguity and representations of androgyny, beside extensive use of theatrics.
It was prefigured by the flamboyant English composer Noël Coward, especially his 1931 song “Mad Dogs and Englishmen”, with music writer Daryl Easlea stating, "Noël Coward’s influence on people like Bowie, Roxy Music and Cockney Rebel was absolutely immense. It suggested style, artifice and surface were equally as important as depth and substance. Time magazine noted Coward’s ‘sense of personal style, a combination of cheek and chic, pose and poise’. It reads like a glam manifesto.” Showmanship and gender identity manipulation acts included the Cockettes and Alice Cooper, the latter of which combined glam with shock rock.
Glam rock emerged from the English psychedelic and art rock scenes of the late 1960s and can be seen as both an extension of, and a reaction against, those trends. Its origins are associated with Marc Bolan, who had renamed his folk duo T. Rex and taken up electric instruments by the end of the 1960s. Often cited as the moment of inception is his appearance on the UK TV programme Top of the Pops in March 1971 wearing glitter and satins, to perform what would be his second UK Top 10 hit (and first UK Number 1 hit), "Hot Love". The Independent states that Bolan's appearance on Top of the Pops “permitted a generation of teeny-boppers to begin playing with the idea of androgyny”. T. Rex's 1971 album Electric Warrior received critical acclaim as a pioneering glam rock album. In 1973, a few months after the release of the album Tanx, Bolan captured the front cover of Melody Maker magazine with the declaration "Glam rock is dead!".