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Kurt Julian Weill (March 2, 1900 - April 3, 1950) was a German composer, active from the 1920s in his native country, and in his later years in the United States. He was a leading composer for the stage who was best known for his fruitful collaborations with Bertolt Brecht. With Brecht, he developed productions such as his best-known work The Threepenny Opera, which included the ballad "Mack the Knife". Weill held the ideal of writing music that served a socially useful purpose.

In 1922 he joined the Novembergruppe, a group of leftist Berlin artists that included Hanns Eisler and Stefan Wolpe. In February 1924 the conductor Fritz Busch introduced him to the dramatist Georg Kaiser, with whom Weill would have a long-lasting creative partnership resulting in several one-act operas. At Kaiser's house in Grunheide, Weill first met singer/actress Lotte Lenya in the summer of 1924. The couple were married twice: in 1926 and again in 1937 (following their divorce in 1933). She took great care to support Weill's work, and after his death she took it upon herself to increase awareness of his music, forming the Kurt Weill Foundation. From November 1924 to May 1929, Weill wrote hundreds of reviews for the influential and comprehensive radio program guide Der deutsche Rundfunk. Hans Siebert von Heister had already worked with Weill in the November Group, and offered Weill the job shortly after becoming editor-in-chief.  Although he had some success with his first mature non-stage works (such as the String Quartet, Op. 8, or the Concerto for Violin and Wind Orchestra, Op. 12), which were influenced by Gustav Mahler, Arnold Schoenberg and Igor Stravinsky, Weill tended more and more to vocal music and musical theatre. His musical theatre work and his songs were extremely popular with the wider public in Germany at the end of the 1920s and the beginning of the 1930s. Weill's music was admired by composers such as Alban Berg, Alexander von Zemlinsky, Darius Milhaud and Stravinsky, but it was also criticised by others: by Schoenberg, who later revised his opinion, and by Anton Webern.  His best-known work is The Threepenny Opera (1928), a reworking of John Gay's The Beggar's Opera written in collaboration with Bertolt Brecht. Engel directed the original production of The Threepenny Opera in 1928. It contains Weill's most famous song, "Mack the Knife" ("Die Moritat von Mackie Messer"). The stage success was filmed by G. W. Pabst in two language versions: Die 3-Groschen-Oper and L'opera de quat' sous. Weill and Brecht tried to stop the film adaptation through a well publicised lawsuit--which Weill won and Brecht lost. Weill's working association with Brecht, although successful, came to an end over politics in 1930. Though Weill associated with socialism, after Brecht tried to push the play even further into a left wing direction, Weill commented, according to his wife Lotte Lenya, that he was unable to "set the communist party manifesto to music."
Kurt Weill