Max Forrester Eastman (January 4, 1883 – March 25, 1969) was an American writer on literature, philosophy and society; a poet, and a prominent political activist. Moving to New York City for graduate school, Eastman became involved with liberal and radical circles in Greenwich Village. He supported socialism and became a leading patron of the Harlem Renaissance, and an activist for a number of liberal and radical causes. For several years, he edited The Masses. With his sister Crystal Eastman, in 1917 he co-founded The Liberator, a radical magazine of politics and the arts.
In later life, however, Eastman changed his views, becoming highly critical of socialism and communism after his experiences during a nearly two-year stay in the Soviet Union in the 1920s, as well as later studies. He was influenced by the deadly rivalry between Leon Trotsky and Joseph Stalin, by which Trotsky was assassinated, as well as the wholesale abuses committed during the Great Purge. Eastman became an advocate of free-market economics and anti-communism, while remaining an atheist and independent thinker. In 1955, he published Reflections on the Failure of Socialism. He published more frequently in National Review and other conservative journals in later life, but always remained independent in his thinking; for instance, he publicly opposed United States involvement in the Vietnam War in the 1960s, earlier than most.