From his debut at New York City’s Metropolitan Opera in 1939 until his death in 1960, baritone Leonard Warren was acclaimed as one of America’s preeminent operatic artists. Among his greatest characterizations were his signature role as Rigoletto and his Macbeth, Simon Boccanegra, Count di Luna in Il Trovatore, Tonio in Pagliacci, Carlo in La Forza del Destino, Scarpia in Tosca and Iago in Otello. Warren's dedication to perfection was legendary. As critic Paul Henry Lang of the New York Herald Tribune wrote, Leonard Warren's "...voice and singing were the triumph of the oldest and most profound traditions of the lyric stage."

Warren’s untimely death at the age of 48, during a Met performance of La Forza del Destino, marked the end of an exceptional career that included performances in the world’s foremost opera houses, including over 600 appearances at the Metropolitan Opera, as well as with other American companies, most notably San Francisco and Chicago. Internationally, Warren performed on the leading operatic stages of Argentina, Brazil, Italy, Mexico, and Russia.