Although it's been on the air for almost 60 years, "The Tonight Show" has had just a handful of regular hosts: Steve Allen, Jack Paar, Johnny Carson, Leno and O'Brien.
He also made regular appearances on The Tonight Show with hosts Jack Paar and then Johnny Carson, The Andy Williams Show and his own TV variety shows - The Jonathan Winters Show and The Wacky World of Jonathan Winters - in the late 1960s and early 1970s.