The German expressionist painter and printmaker was one of the founders of the artists group Die Brücke or "The Bridge", a key group leading to the foundation of Expressionism in 20th-century art. He volunteered for army service in the First World War, but soon suffered a breakdown and was discharged. In 1933, his work was branded as "degenerate" by the Nazis and in 1937 over 600 of his works were sold or destroyed. In 1938 he committed suicide by gunshot. In 1913, the first public showing of Kirchner's work took place at the Armory Show, which was also the first major display of modern art in America. In 1921, U.S. museums began to acquire his work and did so increasingly thereafter.