Mervyn LeRoy Director Robert Taylor Marcus Vinicius Actor Deborah Kerr Lygia Actor Peter Ustinov Nero Actor Leo Genn Petronius Actor Patricia Laffan Poppaea Actor Finlay Currie Peter Actor Abraham Sofaer Paul Actor Marina Berti Eunice Actor Buddy Baer Ursus Actor Felix Aylmer Plautius Actor Nora Swinburne Pomponia Actor Ralph Truman Tigellinus Actor Norman Wooland Nerva Actor Peter Miles Nazarius Actor Geoffrey Dunn Terpnos Actor Nicholas Hannen Seneca Actor Rosalie Crutchley Acte Actor S.N. Behrman Writer Sonya Levien Writer John Lee Mahin Writer Henryk Sienkiewicz Writer Sam Zimbalist Producer William V. Skall Cinematographer Robert Surtees Cinematographer Ralph E. Winters Film Editing Miklós Rózsa Original Music Edward C. Carfagno Art Director Cedric Gibbons Art Director William A. Horning Art Director Hugh Hunt Set Decoration Elso Valentini Set Decoration Herschel McCoy Costume Design