Tower of Power is a horn-based funk/soul band from Oakland, California. In the mid-1960s, 17-year-old tenor saxophonist Emilio Castillo moved from Detroit, Michigan, to Fremont, California. He started a band called the Motowns, specializing in soul music. In 1968, Castillo teamed up with baritone saxophonist Stephen "The Funky Doctor" Kupka and trumpet/trombone player Mic Gillette, moved to Oakland, and began writing original material. They changed the band's name to Tower of Power and began playing frequently in the Bay Area. In 1970, TOP signed a recording contract with Bill Graham's San Francisco Records and quickly released its first album, East Bay Grease.