Having completed a musical apprenticeship in the Irish showbands, and influenced by the increasing popularity of beat groups during the early 1960s, Gallagher formed Taste, a blues rock and R&B power trio, in 1966.

[1] Performing extensively in the United Kingdom, the group played regularly at the Marquee Club, supporting both Cream at their Royal Albert Hall farewell concert, and the blues supergroup Blind Faith on a tour of North America.

[3] Around the same time, he was voted Melody Maker's International Top Musician of the Year, ahead of Eric Clapton.

[3] This Gallagher band performed several TV and radio shows across Europe, including Beat-Club in Bremen, Germany and the Old Grey Whistle Test.

[3] He was David Coverdale's second choice (after Jeff Beck) to replace Ritchie Blackmore in Deep Purple although Gallagher chose to remain a solo artist.

When former members of the Yardbirds (Chris Dreja, Paul Samwell-Smith, and Jim McCarty) reunited to create the band Box of Frogs Gallagher was invited to record with them on their first album.