Production
The Nazis abandoned Rome on June 4, 1944; the Allies occupied the undefended city the next day. Shooting for the film began in January 1945 under precarious conditions, with its style developing from circumstance. The facilities at Cinecittà Studios were unavailable at the time, as they had been damaged in the war and were then currently requisitioned by Allied forces to house displaced persons.
Aldo Venturini, a wool merchant with some capital to invest, was involved in financing the film. After a few days of shooting production had stopped due to lack of cash, and Rossellini convinced Venturini to complete the film as a producer, arguing that it was the only way to safeguard his investment.
New Yorker Rod E. Geiger, a soldier in the Signal Corps who eventually became instrumental in the movie's global success, met Rosselini at a point when the production was out of film. Geiger had access to film - short-ends and complete rolls that might have become fogged, scratched, or otherwise deemed unfit for use - that the Signal Corps regularly threw away. He provided enough of this stock for the picture to be completed.
In order to authentically portray the hardships and poverty of life in Rome under the occupation Rossellini hired mostly non-professional actors; a few exceptions included established stars Fabrizi and Anna Magnani. According to Rossellini, "the situation of the moment guided by my own and the actors' moods and perspectives" dictated what was shot, and he relied more on improvisation than on a script. He also stated that the work was "a film about fear, the fear felt by all of us but by me in particular. I too had to go into hiding. I too was on the run. I had friends who were captured and killed." Rossellini relied on traditional devices of melodrama, such as identification of the film's central characters and a clear distinction between the primary good and evil ones. Only four interior sets were constructed for the more important locations of the film. Production ended in June 1945.
The film's documentary or newsreel style reflects in part different film stocks used in its production. When the Cineteca Nazionale restored the print in 1995 it stated that the original negative consisted of just three different types: Ferrania C6 for outdoor scenes, and the more sensitive Agfa Super Pan and Agfa Ultra Rapid for interiors. The previously unexplained changes in image brightness and consistency are now attributed to inadequate processing, including variable development times, insufficient agitation in the developing bath, and insufficient fixing.
Unlike films made in the early years of the war (when Italy was Germany's ally under Mussolini) that depicted the British, Americans, Greeks, Russians and other allied countries, as well as Ethiopians, communists, and partisans, as antagonists, Rome, Open City was one of the early Italian films of the war to depict the struggle as being against the Germans and Italian fascists. Even though the Allied Invasion of Italy took place in 1943, there is no trace of any Allied presence or imminent arrival in the movie; instead, references are made to it being only "the beginning" of what was characterized as a long struggle ahead, not a Nazi evacuation of Rome that had already occurred.