Because Vittorio De Sica could not understand English, he hired an Italian actor, gave him instructions on how to stand and speak, and asked Montgomery Clift to mimic him. Clift refused.
Upon completion of filming, Jennifer Jones gave Montgomery Clift a Gucci leather briefcase. The clasp on it didn't work, unfortunately. Clift told his friends "It's beautiful, but it doesn't quite work - how like Jennifer".
Because the movie was cut to 63 minutes for American audiences, David O. Selznick had William Cameron Menzies film a special prologue featuring Patti Page, in her movie debut, singing two songs created by Paul Weston from the soundtrack themes by Alessandro Cicognini, "Autumn in Rome" and "Indiscretion." The prologue is not shown with the TV prints or with the various P.D. versions of the film that are circulating, but it has been beautifully restored on the Criterion DVD version of the movie, which itself has been restored back to its original length as "Terminal Station." Patti did not appear on the big screen again until six years later in Elmer Gantry (1960).
David O. Selznick wanted to have a slick romance depicted, whilst Vittorio De Sica wanted to show a ruined romance. In this, he had the full support of the film's star, Montgomery Clift.