Henze was a pupil of the noted German composer Wolfgang Fortner and of René Leibowitz, the leading French composer of 12-tone music. One of Henze’s early works, the Violin Concerto No. 1 (1947), demonstrated his mastery of 12-tone technique, which dominated his writing until 1956. Henze considered his early works, up to his Symphony No. 2 (1949), to be simple, or even primitive, as they depended greatly upon the effectiveness of his melodies.
The opera König Hirsch (1956; The Stag King) marked the beginning of a second period, in which Henze shed serialism (ordered series of notes, rhythms, etc.), revealing a freely inventive and eclectic style. This work showed Henze at maturity, though he was already well established in 1952, when he won the Schumann Prize for his Piano Concerto No. 1 (1950) and finished his second opera, Boulevard Solitude. In 1950–53 Henze was ballet adviser at the Wiesbaden State Theatre, Germany; there he received the impetus for much of his later ballet music, including Ondine (1956), a classical work incorporating jazz elements. Henze’s operas have been widely performed; Elegy for Young Lovers and Das Wundertheater (The Wonder Theatre) were produced in New York City between 1965 and 1970. In his symphonies as well as his stage works, Henze revealed himself as eclectic in his choice of styles—several may be combined in a single work—and romantic in temperament. His Symphony No. 6 for two chamber orchestras (1969) drew on both serialism and elements of traditional tonality utilizing microtonal intervals (smaller than a semitone), amplified instruments, and a large percussion section; it is representative of his works of the 1960s and early 1970s.
Henze took up residence in Italy in 1953. After embracing socialism in the mid-1960s, he expressed his new political affiliation in Das Floss der “Medusa” (“The Raft of the ‘Medusa’ ”), a requiem for Che Guevara and in the opera We Come to the River (1976; in collaboration with Edward Bond). Henze’s book Essays (1964) revealed him as a highly articulate spokesperson for modern music, and Music and Politics: Collected Writings 1953–81 (1982) examined his later belief that music should be politicized.