At the start of the last century a modern tradition of literary radicalism crystallized with inspiring results. From 1900 onward, socialists and bohemians yoked their ideals to become a marathon of forward-thinking activist cultural workers. For the next three decades, writers and intellectuals of the Left, such as Max Eastman (1883–1969), were oracles of enchantment in a world increasingly disenchanted, initially by the international war of 1914–1919 and subsequently by a decline in popular political defiance as capitalism consolidated. Still, the adversarial dream persevered during the violence and later, often in little magazines such as the Masses, Liberator, Seven Arts, and Modern Quarterly. Since the 1920s, literary radicalism meant creativity in the service of an insurrection against political power combined with a makeover in human relationships. With the economic catastrophe of 1929 and the triumph of Nazism in 1933, what might have been a generational succession morphed into a paradigm shift. This previously self-governing literary radicalism was now multifariously entangled with Soviet communism during its most awful hour. An unofficial state of emergency escalated so that a range of journals—this time, New Masses, Modern Monthly, and Partisan Review—once more served as barometers of the depth and breadth of radical opinion. Bit by bit, a strange new ethos enveloped the literary Left, one that blended heroism, sacrifice, and artistic triumph with fifteen years of purge trials in the Soviet Union, mortifying policy shifts in the international Communist movement, and relentless domestic repression against the organized Left in the United States. By the end of this phase, in the reactionary post–World War II years, most adherents of communism (not just the pre-dominant pro-Soviet Communism, but the other varieties of communism such as Trotskyism and Bukharinism) desperately fled their Depression-era affiliations. The upshot was a blurring of the record. This occurred in ways that may have seemed clever for autobiographical concealment (by one-time literary radicals who feared exposure or embarrassment at youthful excesses) but became maddening for future scholars wishing to parse the writers’ former convictions. As literary radicalism passed through the Cold War, 1960s radicalization, the late 20th-century culture wars, and into the new millennium, the tradition was routinely reframed so that it faces us today as a giant puzzle. New research and scholarship emerge every year to provide insights into a very complicated body of writing, but there is a fretful ambivalence about its actual location and weight in literary history. Not surprisingly, most overall scholarly histories, chronicles, and anthologies do not include the category of literary radicalism as a well-defined, principal topic. This is because enthusiasts of the last twenty-five years brilliantly championed the tradition less under the rubric of “literary radicalism” than as the fertile soil for a blooming of gender-conscious, multicultural, and polycentric legacies connected to the Left but primarily rendered as eruptions of American literary modernity onto the world stage. These revisionist images came to us in discrete volumes about black writers, women writers, regional writers, children’s writers, Jewish writers, and so forth. Nonetheless, such celebratory portraits remained in competition with a dark double, a notion that nearly all literary radicals were wanting in artistic value. This skeptical appraisal was entrenched in an older scholarship, a point of view that is partly an aftereffect of the long shadow that the Communist imbroglio cast on its entire legacy.