Chicago was formed under the name The Big Thing on February 15, 1967, with the original lineup comprising guitarist and vocalist Terry Kath, keyboardist and vocalist Robert Lamm, drummer Danny Seraphine, saxophonist Walter Parazaider, trumpeter Lee Loughnane and trombonist James Pankow.

Terry Alan Kath (January 31, 1946 – January 23, 1978) was an American musician and songwriter, best known as a founding member of the rock band Chicago. He played guitar and sang lead vocals on many of the band's early hit singles. He has been praised by the band for his guitar skills and Ray Charles -influenced vocal style.

The group now known as Chicago began on February 15, 1967, at a meeting involving saxophonist Walter Parazaider, guitarist Terry Kath, drummer Danny Seraphine, trombonist James Pankow, trumpet player Lee Loughnane, and keyboardist/singer Robert Lamm.