Martinelli was one of the most famous tenors of the 20th century, enjoying a long career at the Metropolitan Opera in New York City and appearing at other major international theatres.
Outside the United States, Martinelli appeared in Paris and Buenos Aires during his prime but – oddly enough – his native Italy did not hear him at his peak.
In 1937, he returned to London to sing at the Covent Garden in highly acclaimed performances of Otello and as Calaf, opposite the exceptionally powerful English dramatic soprano Eva Turner.
[4] In private life Martinelli was said to be something of a playboy, possessing a charming personality, a wealth of memorable anecdotes and an impressive head of hair that grew silver with age.
Some feature other great Met singers of Martinelli's day, with whom he sang, include the sopranos Frances Alda, Geraldine Farrar and Rosa Ponselle, contralto Louise Homer, baritones Giuseppe De Luca and Lawrence Tibbett, and the bass Ezio Pinza.
Transcription recordings were made of some of his live performances, including a 1935 concert of Beethoven's Missa Solemnis with Arturo Toscanini and the New York Philharmonic Orchestra (which also featured Elisabeth Rethberg, Marion Telva, and Ezio Pinza, broadcast by CBS), a 1939 performance of Verdi's Simon Boccanegra by the Metropolitan Opera, also with Rethberg and Pinza (broadcast by NBC), and various Otellos from the 1930s onwards—including a 1941 version with Lawrence Tibbett, Stella Roman, and Alessio de Paolis, under Ettore Panizza.