Multiliterate Ireland examines a selection of Irish literature to illuminate a legacy of a multilingual history, demonstrated through works that range from past centuries to the present era. This study examines authors who utilized two or more languages in the same poem, play, or work of fiction, also known as "code-mixing" and "code-switching," of primarily English and Irish Gaelic languages, but with the inclusion of others such as Latin, Greek, and French, and examines linguistically and historically why these multiliterate choices were made. Included in this analysis are the history of relationships among the languages, the historical use of multiple languages by Irish and proto-Irish writers, the psycholinguistic and cultural effects of colonial suppression of the language, the attempts at restoration of Irishand the desire for a post-Independence literary legacy in the medium of Irish, and a discussion of certain theories and principles of code-mixing that were developed in the case of its oral use and which may in some cases extend to writing. Along with these historical explanations, examples of multiliterate poetry and prose and the writers who produced them, from the late-17th or early 18-centuries up through contemporary works, are explored in greater depth, and serve to illustrate and highlight various uses of code-switching and code-mixing. Finally, "multiliteracy" as art, or the use of two or more languages as a means of transcendence beyond the ordinary, which is associated with the artistic impulse in general, is explored. This exploration reveals that many Irish writers were akin historically and culturally to artists in various other media whose multi-geographic and multi-linguistic experiences were essential to the development of both enduring and new aesthetic principles. By examining the literature of these Irish writers through the prism of multiliteracy, Multiliterate Ireland attempts to keep at the forefront the authors and their texts, and their decisions to break through the wall of English, or of Irish, to develop an aesthetic that goes beyond a single language, and that creates a language that is at once also many languages.