Jesse L. Lasky, who served as associate producer on this film, also knew the real Enrico Caruso. In 1918, whilst serving as the head of Famous Players (later Paramount) Studio, Lasky had paid Caruso to star in two silent films, My Cousin (1918) and The Splendid Romance (1919), neither of which was commercially successful.
This was the next-to-last completed MGM film under Louis B. Mayer's supervision (the last was Show Boat (1951), released in the summer of that year). A proxy fight soon after would see him removed as the head of the studio he helped to found. He was replaced by his former chief of production, Dore Schary. Mayer ran MGM for 27 years, Schary for barely 6.
Conductor Richard Hageman, who played Carlo Santi in the film, actually knew Enrico Caruso and led several performances with him at the Metropolitan Opera, including the 1918 War Relief Benefit re-created in the film.