In his 1934 book After Strange Gods, T. S. Eliot declared blasphemy obsolete. There could be no blasphemy worth the name, he reasoned, in a world that had lost its faith in God. Yet recent scholarship in sociology and across the humanities has sharply questioned the oncedominant narrative of modern secularization on which Eliot's thesis depends. More importantly, the writers of Eliot's own generation contested that thesis persistently in their poems and fictions. Far from obsolete, that is, blasphemy was in fact a driving force behind literary modernism, and not just in the figurative sense in which scholars have long described the period's artistic provocations as "heretical" or "iconoclastic." This dissertation reveals the extent to which blasphemy, in its full religious sense, accounts for the aesthetic and ideological content of works by writers such as James Joyce, Mina Loy, Langston Hughes, Richard Bruce Nugent, and Djuna Barnes. These and other writers of the period tended to view their modernist experiments as blasphemously godlike efforts to unite Word, Spirit, and Flesh-which helps to explain why the Black Mass and related sacrilegious rites carry such currency in the modernist imagination. It also accounts for the pervasive presence of Christ figures in these texts, usually rendered in highly heterodox forms: as Irish Jews, as lesbian prophets, as lynched black bodies and messianic "New Negroes."Apart from their aesthetic functions, these personae suggest a politics of irreverence that has been largely neglected by studies of religion in modernism. Respecting no division of church and state, modernist writers commonly use the language and tropes of religious desecration to profane all manner of repressive dogmas-including prevailing secular ideologies of race, class, nation, empire, gender, and sexuality. Their blasphemies thus acquire special resonance in the context of broader cultural and ideological concerns that in recent years have enriched the scope of modernist studies. By concluding with a survey of postwar literary blasphemy-and with a look at blasphemy's role in twenty-firstcentury geopolitics-this study proposes still further ways in which the legacies of modernism continue to resonate in the present.