Peter Green founded Fleetwood Mac after leaving John Mayall & the Bluesbreakers. The guitarist and singer formed the new band in London in July 1967 with drummer Mick Fleetwood, slide guitarist Jeremy Spencer, and bassist Bob Brunning.
Green had joined the Bluesbreakers after Eric Clapton’s departure and had already developed a close musical relationship with Fleetwood. When Fleetwood was dismissed from Mayall’s group, Green proposed forming a band together. Green and Fleetwood also wanted bassist John McVie, whose surname supplied the “Mac” in Fleetwood Mac, but McVie initially stayed with Mayall.
The new group debuted as “Peter Green’s Fleetwood Mac featuring Jeremy Spencer.” Bob Brunning played bass only briefly, because McVie soon accepted Green and Fleetwood’s invitation to join permanently. The band’s name had actually been used for an instrumental recorded by Green, Fleetwood, and McVie during free studio time supplied by Mayall.
Danny Kirwan and Jeremy Spencer were important early guitarists, but neither founded the band. Eric Clapton was Green’s predecessor in the Bluesbreakers, not a founder of Fleetwood Mac.