Robin Leonard Trower is an English rock guitarist who achieved success with Procol Harum throughout 1967–1971, and then again as the bandleader of his own power trio known as the Robin Trower Band.

Procol Harum were an English rock band formed in Southend-on-Sea, Essex, in 1967. Their best-known recording is the 1967 hit single "A Whiter Shade of Pale", one of the few singles to have sold more than 10 million copies. Although noted for their baroque and classical influence, Procol Harum's music is described as psychedelic rock and proto-prog with hints of the blues, R&B, and soul.