Let's remember that the movie would never have seen the light of day if
Saul Zaentz had not seen and purchased the film rights to
Peter Shaffer's award-winning
play, a biographical fantasy based on the lives of Wolgang Mozart and Antonio Salieri (Shaffer never claimed to be historically accurate).
Amadeus (Mozart's middle name became the title of the play as it means "Beloved of God," thematically important in the work, and more poetic than "I Hate Mozart") opened in 1979 in London with a production by the Royal National Theatre, with Paul Scofield as Salieri and Simon Callow as Mozart (Callow would appear in the film, not as Mozart, but as theatre manager Emanuel Schikaneder). Peter Hall was the director (All three, along with designer John Bury were nominated for Olivier Awards... but lost out to that year's hit, Nicholas Nickleby).
It soon crossed the Atlantic on Broadway, again with Peter Hall directing, but with Ian McKellen as Antonio Salieri and Tim Curry as Mozart. Both men were nominated for Tony Awards, McKellen won. The show also won a Tony for Best Play (1981), Best Director, and John Bury took home two Tonys for outstanding scenic design and lighting design (he'd also been nominated for costume design). It ran for 1181 performances in New York.
The 1984 film, directed by Milos Forman, starred F. Murray Abraham as Salieri and Tom Hulce as Mozart. Abraham won an Academy Award for Best Actor (beating out Hulce, nominated in the same category), and Forman won the Best Director award. Shaffer won an Academy Award for adapting his own screenplay (The film swept the 1984 Oscars, also taking home Best Picture and awards for Costume Design, Makeup, Art Direction, and Sound).
In 1999, a revival opened on Broadway, (after another Peter Hall production in London at the Old Vic) with a tighter script by Shaffer. (The original play had one ending, which he changed for the movie. Shaffer changed it again for the revival, and worked to humanize Salieri). Hall again directed, and cast David Suchet as Salieri and Michael Sheen as Mozart. Suchet was nominated for a Tony, as was the entire production (for Best Revival).
The "Did Salieri kill Mozart out of jealousy?" theme was not new on stage, it had appeared in Rimsky-Korsakov's opera
Mozart and Salieri which, in turn, was based on Alexander Pushkin's dramatic poem of the same name (1830).