Best known for his “drip paintings,” Jackson Pollock is a leading figure of Abstract Expressionism. Although his gesture-driven splattering and pouring technique marks the height of his artistic achievement, he searched throughout his career to express rather than illustrate emotions. Pollock’s early work shows traces of ethnographic influences, deriving from early encounters with indigenous relics in the Western U.S. At Manual Arts High School in Los Angeles he encountered theosophy, later evoked in his work’s unconscious imagery. Yet when Pollock arrived in New York in 1930, he followed a traditional education in composition at the Art Students League under regionalist painter Thomas Hart Benton. From 1938 to 1942, Pollock was employed by the Works Progress Administration’s Federal Art Project, where he discovered the work of Mexican muralists Diego Rivera (1886–1957), José Clemente Orozco (1883–1949) and David Alfaro Siqueiros (1896–1974). Their method liberated Pollock’s approach to scale and paved the way for his first monumental painting entitled Mural—commissioned by Peggy Guggenheim in 1943. In the late 1940s Pollock came to develop and establish “action painting” as an artistic expression of postwar existentialist mentality. Pollock reached international acclaim during his lifetime and was included in the 1950 Venice Biennale.