Robert Motherwell (January 24, 1915 – July 16, 1991) was an Abstract Expressionist painter. Born in Aberdeen, Washington, he was the youngest of "the New York School" (he coined the term), which also included Jackson Pollock, Mark Rothko, Willem de Kooning, and Phillip Guston .

As an abstract expressionist, his greatest goal was to use the staging of his work to convey to the viewer, the mental and physical engagement of the artist with the canvas. He preferred using the starkness of black acrylic paint as one of the basic elements of his paintings. One of his more well-known techniques involved diluting his paint with turpentine to create a shadow effect.

The Modern Art Museum of Fort Worth houses the largest collection of his works.

With the advent of Pop Art and its concentration on popular culture themes, the art public began to long for the idealism of the Abstract Expressionists. In relation to Andy Warhol’s soup cans, Motherwell's large abstract paintings began to achieve a majesty in the public eye. Motherwell’s politics and spirituality were welcome reminders of a time when one could make art that did not engage the cynicism of a post-modern era. No longer the black sheep of the art world, Motherwell began to enjoy the fruits of years of dedicated work. It seemed, however, for many of the Abstract Expressionists that the newly found appreciation could not counteract the turbulence of those early years—many dying young or taking their own lives. Though somewhat alone, Motherwell committed himself to producing highly experimental work of emotional depth for the rest of his life. On July 16, 1991, at the age of 76 he died: the last of the great Abstract Expressionists. From the 1949 painting, AT FIVE IN THE AFTERNOON, until the end of his life, Motherwell continued his search for a personal and political voice in abstraction. This search produced a body of work that remains a testament to the human soul and its persistence, and to the genre of abstract painting out of which it came.