Trivia

For Groucho Marx' performance of "'Lydia, the Tattooed Lady", additional lyrics were written by E.Y. Harburg exclusively for screenings of the film for Allied servicemen in European war zones. The special lyrics included the line "When she stands the world grows littler; When she sits, she sits on Hitler.' This version of the song was filmed, and included in prints of the film distributed in Great Britain and France, and was greeted with marked enthusiasm during screenings in those countries.

The Marx Brothers had been out of favor at MGM since the sudden death in 1936 of their producer and benefactor Irving Thalberg during the making of A Day at the Races (1937). In the middle of production on this film, longtime Thalberg rival Louis B. Mayer removed songwriters Harold Arlen and E.Y. Harburg and re-assigned them to the prestige MGM production The Wizard of Oz (1939).

Groucho Marx was fond of recounting how the original owner of the gorilla skin used in the film was so incensed after the stunt man wearing it poked ventilation holes in it with an ice pick, that he took his suit and walked off the picture, forcing the producers to hastily rent an orangutan skin as a replacement. For this reason, Groucho claimed, the gorilla gets bigger and smaller from shot to shot. The man in the gorilla suit is, in fact, Charles Gemora, well-known movie sculptor and gorilla artist, wearing his own custom-made suit.

Buster Keaton worked on the film as a gag man. His career was on the downside, and he was forced to work for scale. His complex and sometimes belabored gags (recalled in the book "Groucho, Harpo, Chico and Sometimes Zeppo") did not work well with The Marx Brothers' brand of humor and was a source of friction between the comedian and the brothers. When Groucho called Keaton on the inappropriateness of his gags for the team, Keaton responded, "I'm only doing what Mr. Mayer ("MGM" chief Louis B. Mayer) asked me to do. You guys don't need help."

The scene in the little person's trailer is one of a handful of times Harpo Marx was even vaguely heard on-screen (when he sneezes).