Mario Castelnuovo-Tedesco (3 April 1895 – 16 March 1968) was an Italian composer, pianist and writer. He was known as one of the foremost guitar composers in the twentieth century with almost one hundred compositions for that instrument. In 1939 he immigrated to the United States and became a film composer for Metro-Goldwyn-Mayer for some 200 Hollywood movies for the next fifteen years. He also wrote concertos for Jascha Heifetz and Gregor Piatigorsky.