This chapter surveys the American literary reaction to global warfare in the early twentieth century – primarily World War I – as military events that conditioned, simultaneously, backlashes of political-cultural despair as well as hopes for social regeneration. While it considers well-known classics of the Lost Generation and the malaise shaping its fallout with the mobilization for World War I, it simultaneously problematizes racialized and gendered aspects of those writers’ complaint while examining the war’s differently inflected impact on writing by lesser-known working-class, proto-feminist, and African American novelists. It also considers the advance of modernist interest beyond the Great War into the antifascist struggles of the Popular Front, as well as anticipating the “late” and “post”-modern developments of later war-oriented periods.