Trivia

The plot covers three decades. Father Flaherty ages from his twenties to his fifties.

Actor Christopher Reeve blamed the film's poor box-office and critical reception on the picture's editing. Reeve also once said of this film's failure: "Monsignor should have been a good movie, and it just went off the track for reasons that I don't want to embarrass a lot of people by discussing. The way it was released, the movie is sort of a series of outrageous incidents that you find hard to believe. Since they don't have a focus, and since they aren't justified and explained, they become laughable."

To prepare for his role in this film, actor Christopher Reeve researched religion and Catholicism by visiting the Centre for Alternative Religious Broadcasting in Washington D.C., studying with a Paulist priest at a Paulist's retreat in New Jersey, and for six weeks, he did a residency at the Paulist Fathers Order's Archdiocese in New York City.

When Christopher Reeve was offered this movie, Reeve was keen to play against his 'Superman' super-hero screen persona, which he had also done in Deathtrap (1982) and Somewhere in Time (1980). Reeve once commented after being cast in this film: "I thought the chance to play a morally ambiguous character who was neither clearly good nor clearly bad, someone to whom life is much more complex than the characters I've played previously would be good."

The filmmakers never intended on filming in the Vatican or the Vatican City. The ''Villa Farnese'' in Caprarola, Viterbo, Lazio, Italy doubled for the Vatican. The interiors of this Caprarola Government owned building were comparable to the Vatican's interiors and this location was chosen for exactly this reason. The town of Caprarola in Italy is located about forty miles (or about 65 km) outside of Italy's capital city of Rome which is situated in the same central Italian region of Lazio as Caprarola.