Samuel Osmond Barber II (March 9, 1910 – January 23, 1981) was an American composer, pianist, conductor, baritone, and music educator. One of the most celebrated composers of the 20th century; music critic Donal Henahan stated, "Probably no other American composer has ever enjoyed such early, such persistent and such long-lasting acclaim." Principally influenced by nine years of composition studies with Rosario Scalero at the Curtis Institute and more than twenty-five years of study with his uncle, the composer Sidney Homer, Barber's music usually eschewed the experimental trends of musical modernism in favor of utilizing traditional 19th-century harmonic language and formal structure that embraced lyricism and emotional expression. However, elements of modernism were adopted by Barber after 1940 in a limited number of his compositions, such as an increased use of dissonance and chromaticism in the "Cello Concerto" (1945) and "Medea's Dance of Vengeance" (1955), and the use of tonal ambiguity and a narrow use of serialism in his "Piano Sonata" (1949), "Prayers of Kierkegaard" (1954), and "Nocturne" (1959).