Keith Hartley was born in Preston, Lancashire. His career began as the replacement for Ringo Starr as drummer for Rory Storm and the Hurricanes, a Liverpool-based band. Subsequently he played and recorded with The Artwoods, then achieved some notability as John Mayall's drummer (including his role as the only musician, other than Mayall, to play on Mayall's 1967 "solo" record The Blues Alone. He then formed The Keef Hartley (Big) Band, mixing elements of jazz, blues, and rock and roll; the group played at Woodstock in 1969.
They released five albums, including Halfbreed and The Battle of North West Six (characterised by a reviewer for the Vancouver Sun as "an amazing display of virtuosity"). After that Hartley released a 'solo' album (Lancashire Hustler, 1973) and then he formed Dog Soldier with Miller Anderson (guitar), Paul Bliss (bass), Derek Griffiths (guitar) and Mel Simpson (keyboards). They released an eponymous album in 1975, which had a remastered release in early 2011 on CD on the Esoteric label.
In 2007, Hartley released a ghostwritten autobiography, Halfbreed (A Rock and Roll Journey That Happened Against All the Odds). Hartley wrote about his life growing up in Preston, and his career as a drummer and bandleader, including the Keef Hartley Band's appearance at Woodstock.
Hartley died on 26 November 2011, aged 67, at Royal Preston Hospital in Preston.