 The film was shot clandestinely in Rome in 1944 during what is known  in History as the Republic of Salò, when Mussolini was deposed and  the country occupied by the Germans. At that time, all cinematic  activity was to be transferred North (Venice) but many actors and  technicians decided to stay. Some were able to obtain work permits  delivered by the Vatican, enabling them to go about and work in the  Rome completely freely. Those who were not able to get such document  had no choice but to work clandestinely.