Jackson Pollock's Mural , created early in his career in 1943, is a vast panorama spanning a 6-metre-long canvas - the largest painting he ever made. Mural marked a watershed for Pollock: a presentiment of the epic scale, complexity, energy and ambition of the work ahead. David Anfam considers the manifold influences on Pollock that led to this landmark achievement - including the context of the American West, his hitherto little-known relationship with Clyfford Still and the importance of wartime action photography. He also traces the explosive magnetism Mural exerted over the emergent Abstract Expressionists and its legacy for painters and sculptors as diverse as Mark Rothko, Robert Motherwell, David Smith, Richard Serra and Brice Marden. Indeed, the work's wider impact on post-war American art is comparable to that of Picasso's Demoiselles d'Avignon on European modernism in the first half of the twentieth century.