Over the nineteenth century, the popular and the scientific understanding of idiocy changed in conjunction with shifts in social concerns and the emergence of new discourses. An examination of representations of idiocy over the century foregrounds the manner in which the condition was given shape and meaning. The dissertation traces the history of the idea of intellectual disability in England from the start of the nineteenth century up to the initial articulation of eugenics, and argues that the idea of intellectual disability acquired new significance in the Victorian era, eventually stabilizing somewhat with the notion of the idiot as degenerate. Political, gender, economic, religious, literary and scientific discourses interact to weave a notion of what intellectual disability means and how it should be interpreted. This dissertation examines the ways that idiocy is constructed by these discourses, and to what ideological purpose, by reading critically texts involved in the construction of the notion. These texts include Wordsworth’s “The Idiot Boy,” Dickens’ Barnaby Rudge, Scott’s Waverley, and Gaskell’s “Half a Life-time Ago,” among other literary works, as well as medical, scientific and sociological writings. The dissertation is organized thematically and, for the most part, chronologically to sketch out a cultural history of the idea of idiocy, with an emphasis on delineating the factors that shaped perceptions (the idiot as holy fool, as innocent, or as degenerate), as well as on the ideological significance of the notion of idiocy. Throughout the dissertation, special emphasis is placed on the relation of intellectual disability to gender notions, and the varying interpretations of the significance of intellectual disability when associated with men or women.