The Polka Tulk Blues Band from Birmingham changed their name to Earth in 1969, but this caused problems as there was already a band with that name. So they had to find another name and decided on Black Sabbath, inspired by a film starring Boris Karloff. Numerous successful pub gigs across England and an appearance on the music show Top Gear at the end of 1969 prompted the Vertigo label to record an album with the band. Ozzy Osbourne (vocals, harmonica), Tony Iommi (guitar), Geezer Butler (bass) and Bill Ward (drums) were given exactly two days to record and mix the album. In the end, however, they only needed just 12 hours for the recordings, playing their live set under the direction of producer Rodger Bain and sound engineer Tom Allom, with almost no overdubs. The very next day they already had to perform in Switzerland.

Their eponymous debut album was released in February 1970 with the now-famous cover design by Keith MacMillan, known as Keef, whose dark and eerie photographs helped to visualise the horror of the new musical genre heavy metal. It is widely regarded as the first album of this new style of rock music. Further groundbreaking albums were to follow: Paranoid (1970) and Master Of Reality (1972). British first pressing originals in top condition, featuring the imprint „A Philips Record Product“ on the B-side of the label as well as the erroneous copyright warning „Copyright subsists in all Stereo recordings…“, are extremely sought-after worldwide and therefore change hands for over £4,000!