The dissertation examines the role played by cross-national, cross-lingual and cross-cultural exchanges in the development of Italian literature at the turn of the twentieth century. It challenges the mono-nationalist paradigm that still dominates literary history despite broader theorizations in fields such as migration and postcolonial studies. The dissertation employs an interdisciplinary approach to argue that many of the most exciting and influential developments in post-Unification Italian literature, even from a formal and technical standpoint, were born out of cultural and linguistic miscegenation. To make this case, it focuses on a cluster of writers understood as ‘Italian’ within a paradigm marked by the opposing forces of appartenenza and sradicamento, which, it argues, simultaneously concurred to the identity formation and artistic practice of writers working in and around Italy at the turn of the twentieth century. The project examines works by canonical writers alongside the marginalized voices of women and migrant authors. It therefore results in a radical reconfiguration of the literary canon. Chapter One argues that Gabriele D’Annunzio culturally embodies a liminal posture that blurs the lines between center and margin, local and foreign and that many of his works display resistance to his bombastic rhetoric of italianità. By analyzing the novel Il Fuoco and the play La Nave, I claim that the foreign plays an important part in D’Annunzio’s nation constructing endeavor and that both works stage his negotiation between cosmopolitan and purist ideals of citizenship and art. Chapter Two argues that Marinetti articulated a poetics of sradicamento, by which I identify a violent and anti-bourgeois type of cosmopolitanism, able to paradoxically coexist with militant political nationalism. The chapter contends that the colonialist novel Mafarka le futuriste envisions continuity between Italian and African populaces, at odds with the eugenicist ideology at the root of other colonizing discourses and that poems such as “Battaglia Peso + Odore” and “Zang Tumb Tumb. Adrianopoli Ottobre 1912” openly question the foundational equation between national belonging and linguistic homogeneity. Chapter Three examines the poetry of Italian American Emanuel Carnevali as the translingual production of an author placed at the crossroads of nations, languages and cultures. It tracks his attempts at self-construction as an “American poet” and their failure, as his body of work reflects his physical body as a disabled, queer, migrant author, and is thus subject to dynamics of othering and de-humanization. Chapter Four argues that both Annie Vivanti and Amelia Pincherle Rosselli opposed the aggressively belligerent rhetoric of nationalism. The chapter contends that Vivanti conceptualized what I call the “performativity of nationality” in direct opposition to coeval notions of ethnic and racial purity, while Rosselli engaged with matters of national belonging and the possibility of cosmopolitanism, despite maintaining reservations about its viability.