Quo Vadis (1951 film) producer Sam Zimbalist
Casting
The film was originally cast in 1949 with Elizabeth Taylor as Lygia and Gregory Peck as Marcus Vinicius. When the production changed hands the following year, the roles went to Deborah Kerr and Robert Taylor. Elizabeth Taylor had an uncredited cameo role as a Christian in the Circus prisons.
Although most of the cast was British and a few Italian (Marina Berti, Alfredo Varelli, Roberto Ottaviano), Robert Taylor was certainly not the only American. Others included Buddy Baer (Ursus), Peter Miles (Nazarius), Arthur Walge (Croton), and William Tubbs (Anaxander). Also, several were among the uncredited cast; perhaps the most notable of these was 70-year-old Irish-American character actor Richard Garrick as the public slave who stands behind Marcus in his Triumph chariot, holding a victory laurel above his head, and repeating "Remember thou art only a man." Ustinov recalled how he was cast as Nero in 1949: 
"An exciting proposition came my way when I was 28 years old. MGM were going to remake Quo Vadis, and I was a candidate for the role of Nero. Arthur Hornblow [Jr] was to be the producer, and I was tested by [the director] John Huston. I threw everything I knew into this test, and to my surprise, John Huston did little to restrain me, encouraging me in confidential whispers to be even madder. Apparently the test was a success, but then the huge machine came to a halt, and the project was postponed for a year. At the end of the year, the producer was Sam Zimbalist and the director Mervyn LeRoy. They also approved my test, but warned me in a wire that I might be found to be a little young for the part. I cabled back that if they postponed again, I might be too old, since Nero died at 31. A second cable from them read 'Historical Research Has Proved You Correct Stop The Part Is Yours'.Clark Gable turned down the role of Marcus Vinicius very early in the film's production history because he thought he would look ridiculous in Roman costumes.
Sophia Loren appeared in the film as an extra. Italian star Bud Spencer (real name: Carlo Pedersoli) also had an uncredited extra role as a Praetorian guardsman inside Nero's summer palace at Antium. (He answers Nero, but his voice may be dubbed.)
Audrey Hepburn, still widely unknown when the film was released, was considered for the part of Lygia. Director Mervyn LeRoy wanted to cast her, but the role went to established MGM contract star Deborah Kerr, instead. Wardrobe stills of her in costume for the film still exist.Patricia Laffan was selected by the producer and director for the major role of Poppaea after they watched a screen test she made for a smaller part in the film.At 107 years of age (on 31 August 2021), Italian actor Alfredo Varelli (Lucan) may be the oldest surviving person associated with the film.Ustinov relates in his autobiography Dear Me that director Mervyn LeRoy summarized the manner in which he envisioned Ustinov should play the Emperor Nero, very salaciously, as
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