On the DVD, Taina Elg says the original cast was supposed to include Cyd Charisse as the American girl, Leslie Caron as the French girl, and Kay Kendall as the English girl. Charisse decided to do La belle de Moscou (1957) instead, so Mitzi Gaynor took her part. At one point, Kendall didn't want to do the film and Elg was tested for her role. Kendall took the part after all, but then Caron withdrew. Elg was tested then for THAT character and received her first major film role. Jean Simmons and Carol Haney were also considered for film roles.
This was the last complete film score by Cole Porter and the next-to-last score of his career. He later created several musical numbers for the film version of his Broadway hit "Silk Stockings."
The last movie Gene Kelly made for MGM under his contract, which began in 1942. It wasn't until the documentary Il était une fois Hollywood (1974) that he would appear in another MGM musical.
Heard in the background between the stage performances is a snippet of "Be a Clown". Cole Porter wrote this for Le pirate (1948), and he wrote the rest of "Les Girls" songs.
Taina Elg had just given birth to her only son Raoul when she got the role of Angèle Ducros, which originally was planned for the French Leslie Caron.