Jimmy Witherspoon was a blues shouter with hit records dating back to the mid 40s. His popularity declined in the late 50s due to the explosion of rock and roll. Like many of his blues contemporaries, Witherspoon enjoyed a resurgence in the 60s due to the heavy influence of American blues on popular British bands of the era.
In early 1971, former Animals frontman Eric Burdon, then fronting War, collapsed on stage and withdrew from the rest of War's tour, ultimately leaving the band. War went on to become one of the most popular acts of the 70s, while Burdon withdrew to record a blues album with Jimmy Witherspoon called Guilty!. The Witherspoon/Burdon appearance at Celebration of Life was part of a tour to promote the album.