This is the only film in which Julie Andrews appeared in between her iconic performances in Mary Poppins (1964) and The Sound of Music (1965). Andrews would later say she was particularly happy about the timing of this film's release, and its commercial and critical successes. The actress speculated that if she had appeared in the two well-known family musicals back-to-back that she risked being type-casted, which could have ultimately hurt her career.
According to screenwriter Joe Eszterhas's 2004 autobiography "American Animal", producer Martin Ransohoff removed director William Wyler from the picture as Wyler wanted to change Paddy Chayefsky's script. It was a rare instance in which a producer supported a screenwriter over a director, particularly one of Wyler's caliber. As Chayefsky was known to have guarantees written into his contracts protecting his scripts, Ransohoff may have had no choice but to replace Wyler with Arthur Hiller.
The D-Day landing scenes were filmed on Mandalay Beach in Oxnard, California. In the behind-the-scenes documentary "Action on the Beach" (1964), the Mandalay power generating station, then operated by Southern California Edison can be seen in several shots. The plant, still operating in 2010, opened in 1959.
The author of the novel, "The Americanization of Emily", William Bradford Huie, states in the foreword to the novel that: "The Americanization of Emily, like The Revolt of Mamie Stover, is from the war memoirs of Lieutenant Commander James Monroe Madison, USNR. All characters are fictitious." The novel's protagonist is Jimmie Madison. That character is named Charlie Madison and is played by James Garner in this movie, and is named Jim Blair and is played by Richard Egan in The Revolt of Mamie Stover.
The original paper dust jacket of the first edition of the novel "The Americanization of Emily" states that it is "The further adventures of Lieutenant Commander James Monroe Madison of The Revolt of Mamie Stover".