John Michael "Ozzy" Osbourne is an English musician and media personality. He rose to prominence during the 1970s as the lead singer of the heavy metal band Black Sabbath, during which period he adopted the nickname "Prince of Darkness".

Black Sabbath were an English rock band formed in Birmingham in 1968 by guitarist Tony Iommi, drummer Bill Ward, bassist Geezer Butler and vocalist Ozzy Osbourne. They are often cited as pioneers of heavy metal music. The band helped define the genre with their first three albums Black Sabbath, Paranoid and Master of Reality (1971). Following Osbourne's departure in 1979, the band underwent multiple line-up changes, with Iommi being the only constant member throughout their history.