Joel McCrea
Writer-director Preston Sturges never considered any other actor for the character bearing more than a passing resemblance to himself. John L. Sullivan is a hotshot director of comedy films—like Sturges—and so it must say something quite telling about the attributes of actor Joel McCrea that he wrote the part with McCrea in mind and never entertained making the film with anyone else in the role.
Veronica Lake
Unlike the case with the male leader, Sturges did not exactly get his everything he wanted with his female lead. The director did not write the part with anyone in particularly in mind, preferring instead to discover the perfect match through the audition process. Although Barbara Stanwyck and tragic Hollywood figure Frances Farmer were also in contention, the part was eventually played the diminutive actress with the famous peek-a-boo hairstyle, Veronica Lake. What most viewers don’t realize is that Lake was more than six months pregnant throughout the filming
William Demarest
Like many of the other actors to appear in the film, William Demarest was part of director Preston Sturges’ regular troupe of actors that appeared in most of his films. A character actor with a long list of credits in Hollywood, Demarest is probably most often associated with his character on the TV sitcom My Three Sons. Six years after making Sullivan’s Travels, Demarest would receive his only Academy Award nomination for Best Supporting Actor in The Jolson Story playing a character named Steve Martin.
Robert Greig
Playing the underling who is one of the few men with the guts to warn Sullivan that his idea for travels is perhaps not the best idea he’s ever had is Robert Greig. Greig—yet another of the Sturges stock company of actors—hits the perfect note as the menial man of lowly service who dares to reveal his superior wisdom.
Eric Blore
Another member of the Sturges troupe was Eric Blore whose valet provides much the same purpose as Greig’s butler: showing how the common man has superior common sense to the arty and business types running Hollywood. Blore’s voice may be more familiar than his face: he gave voice to Mr. Toad in the Disney animated version following his wild ride.