American painter Jackson Pollock (1912-1956) was the leading figure in abstract expressionism, a style that evolved after World War II and radicalized the history of American painting and modern art in general.

Before World War II modern painting was dominated by European developments. Although American painters were aware of them, they generally did not participate in their origin or contribute significantly to their evolution. With the advent of World War II the mainstream of modern art shifted dramatically. The numerous European artists who sought refuge in the United States exerted a profound influence on younger American painters and sculptors. From this cultural collision emerged a style whose roots lay abroad--for the most part in cubism and surrealism--but whose look and meaning were without precedent. The style became known as abstract expressionism, or "action" painting, because it frequently resulted from a direct and unpremeditated relationship between an artist and...