John Michael "Ozzy" Osbourne was born in aston, Birmingham, England, on 3 December 1948. His father Jack worked shifts as a tool maker at the G E c His mother Lillian worked for the car components firm Lucas. John was the fourth of six children. Ozzy had two brothers (Paul and Tony) and three sisters (Jean, Iris and Gillian); they lived in a small two-bedroom home at 14 Lodge Road in aston. The nickname "Ozzy" was first used when he was in primary school. although called "John" by his first wife Thelma, Osbourne states that it has been a long time since he's recognised himself when called by his formal name.

Osbourne grew up dealing with dyslexia and other learning disabilities General abuse from teachers at Prince albert Road Junior School, and Birchfield Road Secondary Modern School in Perry Barr made his childhood difficult for him. Drawn to the stage, Osbourne took part in school plays such as The Pirates of Penzance. Upon hearing their first hit single at age 14, he became a great fan of The Beatles. He left school at 15 and was then employed as a construction site labourer, trainee plumber, apprentice toolmaker, car factory horn-tuner and slaughterhouse worker. He spent six weeks in Winson Green Prison when he was unable to pay a fine after being found guilty of burglary of a clothes shop.

In late 1967, Geezer Butler formed his first band "Rare Breed" with Osbourne. The band played two shows then broke up. Separated for a time, Osbourne and Butler reunited in Polka Tulk Blues along with guitarist Tony Iommi and drummer Bill Ward. They renamed themselves Earth, but after being booked in error instead of a small-time English circuit band with the same name, they decided to change their name again. They finally chose the name Black Sabbath in early 1969 based on a film directed by Mario Bava, starring Boris Karloff. The band had noticed how people enjoyed being frightened, and, inspired, Iommi and his partners decided to play a heavy blues style of music laced with gloomy sounds and lyrics. While recording their first album in a castle, Geezer read an occult book and had a dream of a dark figure at the end of his bed. Butler told Osbourne about the dream and together they wrote the lyrics to "Black Sabbath", one of their first songs in a darker vein.