From Wikipedia:
Jackie Gleason's first variety series was aired on the DuMont Network under the title Cavalcade of Stars. After previous host Jerry Lester quit the show in June 1950 (soon to become the star of NBC's first late-night series, Broadway Open House), Gleason — who had made his mark on the first television incarnation of The Life of Riley sitcom — stepped into Cavalcade on July 15, 1950, and became an immediate sensation. The show was broadcast live, in front of a theater audience, and offered the same kind of vaudevillian entertainment common to early-TV revues. Jackie's guests included New York-based performers of stage and screen, including Bert Wheeler, Smith and Dale, and Vivian Blaine. Production values were decent but not spectacular, owing to DuMont's humble facilities and a thrifty sponsor (Quality Drugs, representing most of the nation's neighborhood drug stores).
In 1952, CBS president William S. Paley offered Gleason a much higher salary, with which DuMont could not compete. The series was retitled The Jackie Gleason Show and premiered on CBS on September 20, 1952.[1]
While much of DuMont's programming archive was later destroyed after they ceased broadcasting[2], a surprising number of Cavalcade of Stars episodes survive, including several episodes at the UCLA Film and Television Archive. At least 14 of the Jackie Gleason episodes survive at the Paley Center for Media, though the exact number of surviving episodes is unclear (see online catalog).
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