The working titles of this film were Barnum, P. T. Barnum and The Great Barnum. The Twentieth Century-Fox Produced Scripts Collection at the UCLA Theater Arts Library contains a full treatment by John Huston, dated 9 Aug 1933. In his autobiography, Huston states that after his contract with Universal expired, Darryl Zanuck, 20th Century Pictures' Vice-President in charge of production, gave him two volumes of a current biography of Barnum to read and hired him to write a script based on Barnum's life. Huston writes that he saw in Barnum's "wild energy, boundless vulgarity and casual assumption that he was the shrewdest man alive, an exemplification of the nineteenth-century American dream of conquest and Manifest Destiny." Zanuck, according to Huston, did not care for his approach to the subject, and "wanted to make changes that were out of keeping with my original idea." Huston then suggested that it would be better to start with another script, and Zanuck took him off the project. Huston considered his script to be far better than the one used for the film. Although Huston states that apparently his script no longer exists, the Produced Scripts Collection contains a 115-page treatment by Huston. In addition, the Collection contains a synopsis by Huston dated 17 Oct 1933, which followed a conference with Zanuck. The synopsis contains many sequences that are in the final film.
       Zanuck subsequently put Associate Producer Raymond Griffith to work on the screenplay, and in a document dated 7 Feb 1934, following a treatment by Griffith, Zanuck states his intentions concerning the proposed film's style: "First, last and always our Barnum should be a comedy, a boisterous, loud-mouthed comedy with a tear. It should be the kind of a picture The Bowery was, full of laughs, full of punch and excitement, yet having a couple of sentimental, pathetic notes. It should not be the kind of picture Silver Dollar was. Silver Dollar made the artistic and box office mistake of taking itself too seriously. It was the Great Drama, the great baloney picture of the rise of a great American character. Audiences don't want to see history or costumes or learn anything about great men unless they can laugh while they are learning....[Barnum] is not a historical, stretched out, ponderous narrative like Silver Dollar that tried to take itself so seriously that audiences think they are being lectured to instead of being hysterically entertained. Do not worry about historical facts or times or dates or truth. We should write a picture for fiction and entertainment...." [The Bowery (see above), 20th Century Pictures' first production, told the fictionalized story of legendary New York characters at the turn of the century, while Silver Dollar (see below), a 1932 First National production, made while Zanuck was production chief at that studio, was based on the life of Colorado silver magnate Horace A. W. Tabor.]
       Zanuck subsequently assigned Gene Fowler to write a treatment and then a continuity before appointing Bess Meredyth to collaborate with Fowler on the screenplay. In a modern source, Fowler states that he learned more about screenwriting from Meredyth than from anyone else in the studios. Fowler and Meredyth's screenplay was published in book form in 1934. NYT commented that the film "is almost sober by comparison with the published edition of the Fowler-Meredyth screen play, with its hilarious marginalia." The pressbook in the copyright descriptions states that the screenplay was the first to be published in book form for the general public.
       Virginia Bruce's songs were dubbed by Frances White. NYT commented, "The dubbing process by which Miss Bruce appears to be singing a lyric soprano is the most convincing that this reporter has ever seen." According to a HR news item, Edna May Oliver declined Zanuck's offer of the role of "Mrs. Barnum" because she would have had to play alternate days with her role in M-G-M's David Copperfield (see above). According to the pressbook, R. E. "Tex" Madsen, who played the Cardiff Giant, was eight-feet four-inches tall, and George and Olive Brasno, who played Tom and Lavinia Thumb, were brother and sister. The running time in MPH for the preview in Hollywood was 105 minutes. Subsequent listings for running times vary considerably.