Forrest Cowles "Bud" Sagendorf became the first and only assistant of 'Thimble Theatre' creator Elzie Segar after his studies at the Santa Monica High School. Sagendorf assisted Segar on 'Thimble Theatre' and its companion strip 'Sappo' from 1931 until the artist's death in 1938. King Features Syndicate hired other artists to continue the strip however, but did keep Sagendorf to draw marketing material starring 'Popeye'.
Between 1946 and 1962, he drew over 100 original stories for the Dell comic books starring 'Popeye', as well as their back-up feature 'Sherm'. He eventually took over the writing and the art of the 'Thimble Theatre' strip for King Features Syndicate in 1959.
Failing eyesight forced him to leave daily strip to Bobby London in 1986, but Sagendorf continued the weekly comic until his death in Greater Sun Center, Florida, in 1994. The Sunday page was then taken over by Hy Eisman, while the syndicate continues to run reprints of Sagendorf's dailies. Sagendorf was the artist with the longest run on the 'Thimble Theater'/'Popeye' comics, surpassing the series creator. It is his version of the character that is best known by the general public. A collection of his best work was edited by Craig Yoe and published by Idea & Design Works Llc in 2011.
Two Popeye panels by Sagendorf inspired Roy Lichtenstein's 'Popeye' and 'Wimpy (Tweet)' (both from 1961).