Russian-born American painter Mark Rothko is best known for abstract paintings in which soft-edged rectangles of color seem to float weightlessly against undefined backgrounds. A major figure in the abstract expressionism movement, Rothko used color to convey a range of emotion and what the artist described as a religious experience. Rothko attended Yale University, New Haven, on a scholarship from 1921 to 1923. That year, he left Yale without receiving a degree and moved to New York. In 1925, he studied under Max Weber at the Art Students League. He participated in his first group exhibition at the Opportunity Galleries, New York, in 1928. In the early 1940s, he worked closely with Gottlieb, developing a painting style with mythological content, simple flat shapes, and imagery inspired by primitive art. By mid-decade, his work incorporated Surrealist techniques and images. Peggy Guggenheim gave Rothko a solo show at Art of This Century in New York in 1945. In 1947 and 1949, R