The H.R. Pufnstuf character was originally created for the HemisFair '68 world's fair in 1968, where the Kroffts produced a show called Kaleidescope for the Coca-Cola pavilion. The character's name was Luther and he became the symbol of the fair.
Paul Simon successfully sued the Krofft brothers for plagiarizing his song, "The 59th Street Bridge Song (Feelin' Groovy)," in the series' theme song. As a result, Simon was given a writing credit in the series for the theme song.