Mark Rothko (1903-1970) was a celebrated Abstract Expressionist best known for his large, iconic 'colour field' paintings with blocks of glowing colour. Rothko devised a unique method to achieve luminosity in his work by applying thin washes of oil paint. Obsessed by colour, Rothko carefully composed his paintings to evoke a variety of emotions in the viewer. His soft, rectangular forms seem to float gently on the canvas. Rothko made an impressive contribution to American art and is considered one the most significant artists of the 20th century.