The poetry, prose, and personality of Walt Whitman have attained a truly global circulation, and scholarship continues to reveal his complex and lasting impact on literature, art, and politics around the world. This dissertation reveals Walt Whitman's extensive appropriation by the Latin American avant-garde, an artistic current that encompassed dozens of regional, national and transnational vanguardia movements across the Americas from roughly 1918 through the late 1930s. My work tells the story of how these pugnacious literary and artistic communities used Whitman as the raw material for a self-consciously "modern" art, as they circulated, adapted, and repurposed the US poet and his texts. The dissertation moves from south to north, beginning in Chile, proceeding to Nicaragua and Mexico, and ending with Latino writers in the United States. "Out of Place: Walt Whitman and the Latin American Avant-Gardes" argues that the literary and political appropriation of Whitman becomes a part of these movements' active participation in the hemispheric and global conversation of their day. What these aggressive avant-garde groups find useful, provocative, or generative in Whitman, then, offers us a unique perspective that cannot be left out of American literary studies. For as they wrestle with Whitman and the concept of "America," as they adapt Whitman into their notions of art, of nation and of language, and as they read him against the backdrop of globalization and modernity, a new Walt Whitman emerges, a vanguardista Whitman who sheds new light on the enduring relevance of his own radical project of making a poetry for the Americas.