The Spencer Davis Group was formed in 1963 in Birmingham when Welsh guitarist Spencer Davis recruited vocalist and organist Steve Winwood and his bass playing brother Muff Winwood. The group was completed with Pete York on drums. Originally called the Rhythm and Blues Quartette, the band performed regularly in the city. In 1964 they signed their first recording contract after Chris Blackwell of Island Records saw them at an appearance in a local club; Blackwell also became their producer.

The Spencer Davis Group – particularly its incarnation with Steve Winwood – proved to be influential, with many of the band's songs covered by other artists over the years. Notable among these are Chicago's 1969 version of "I'm a Man"; The Allman Brothers Band's 1969 take of Davis' instrumental "Don't Want You No More"; Three Dog Night's 1970 recording of "Can't Get Enough of It"; and The Blues Brothers' 1980 recording of "Gimme Some Lovin". The Grateful Dead also covered Spencer Davis Group material in live performance on occasion, and Spencer Davis himself performed "I'm a Man" with the Grateful Dead at a 1989 performance at Los Angeles' Great Western Forum.............from Wikipedia.