remainder of the twentieth century. The exhibition had a twofold effect of communicating to American artists that artmaking was about expression, not only aesthetics or realism, and at the same time showing that Europe had abandoned its conservative model of ranking artists according to a strict academic hierarchy. This encouraged American artists to find a personal voice, and a modernist movement, responding to American civilization, emerged in New York. Alfred Stieglitz (1864–1946), photographer, Charles Demuth (1883–1935) and Marsden Hartley (1877–1943), both painters, helped establish an American viewpoint in the fine arts. Stieglitz promoted cubists and abstract painters at his 291 Gallery on 5th Avenue. The Museum of Modern Art, founded in 1929, became a showcase for American and international contemporary art. By the end of World War II, Paris had declined as the world's art center while New York emerged as the center of contemporary fine art in both the United States and the world. In the years after World War II, a group of young New York artists known as the New York School formed the first truly original school of painting in America that exerted a major influence on foreign artists: abstract expressionism. Among the movement's leaders were Jackson Pollock (1912–1956), Willem de Kooning (1904–1997), and Mark Rothko (1903–1970). The abstract expressionists abandoned formal composition and representation of real objects to concentrate on instinctual arrangements of space and color and to demonstrate the effects of the physical action of painting on the canvas. New York's vibrant visual art scene in the 1950s and 1960s also defined the American pop art movement. Members of this next artistic generation favored a different form of abstraction: works of mixed media. Among them were Jasper Johns (1930– ), who used photos, newsprint, and discarded objects in his compositions. Pop artists, such as Andy Warhol (1930–1987), Larry Rivers (1923–2002), and Roy Lichtenstein (1923–1997), reproduced, with satiric care, everyday objects and images of American popular culture—Coca-Cola bottles, soup cans, comic strips. Today New York is a global center for the international art market. The Upper East Side has many art galleries, and the downtown neighborhood of Chelsea is known for its more than 200 art galleries that are home to modern art from both upcoming and established artists. The industry is also present in neighborhoods known for their art galleries such as DUMBO, where dealers representing both established and up-and-coming artists compete for sales