Short answers, pulled from the story.
Black Sabbath formed in Birmingham in 1968, founded by guitarist Tony Iommi, drummer Bill Ward, bassist Geezer Butler, and vocalist Ozzy Osbourne. The group adopted the Black Sabbath name in August 1969, having previously performed as the Polka Tulk Blues Band and then Earth.
Black Sabbath had sold over 70 million records as of 2013, making them one of the most commercially successful heavy metal bands in history.
Iommi fired Osbourne on the 27th of April 1979 after years of mounting substance abuse made the band unable to function. The band would come up with song ideas but Osbourne showed little interest and refused to sing them. Iommi concluded the only options were to fire Osbourne or break the band up entirely.
Ronnie James Dio, formerly of Rainbow, replaced Osbourne in 1979 and recorded three albums with the band: Heaven and Hell (1980), Mob Rules (1981), and the live album Live Evil (1983). Dio left in November 1982 and later died in 2010. Other vocalists included Ian Gillan, Glenn Hughes, and Tony Martin.
Black Sabbath won two Grammy Awards for Best Metal Performance and received a Grammy Lifetime Achievement Award. They were inducted into the UK Music Hall of Fame in 2005 and the Rock and Roll Hall of Fame in 2006. MTV ranked them the Greatest Metal Band of All Time.
Black Sabbath's final concert, titled Back to the Beginning, took place at Villa Park in Birmingham on the 5th of July 2025. It was conceived as the last performance for both the band and Ozzy Osbourne as a solo artist. Osbourne died seventeen days after the performance.