The production got permission to shoot the scenes in a real convent (Fossanova Abbey in Priverno, Latina, Italy) because the religious were not told the plot precisely.
The opening credits state that the movie is 'Based on authentic 16th Century records and a story by STENDHAL'.
British actor Edmund Purdom ("The Egyptian" 1954) provides the dubbed dialogue for Luc Merenda in the English speaking print.
Italian censorship visa # 61797 delivered on 24-1-1973.