Mark Rothko was a Russian-born American painter and a founding member of the abstract expressionist movement. He is known for his large-scale paintings consisting of colored rectangles or squares arranged in horizontal tiers on a solid colored background. In the 1940s, Rothko began experimenting with mythological themes and different techniques that led to his signature format of floating color fields. By the 1950s, his paintings typically featured only a few large rectangles of color to achieve a meditative, transcendent experience for the viewer. Rothko sought to express emotional and spiritual themes through his abstract works and did not want to explain his paintings, believing interpretations should come from the viewer's own experience.