This dissertation examines textual and literary culture in England during the first half of the fifteenth century and the nascent canon of English literature emerging in the decades after Chaucer's death in 1400. Its focus is the manuscripts of John Shirley (ca. 1366-1456), the bureaucrat and bibliophile whose autograph manuscripts contain unique copies of many of Geoffrey Chaucer's and John Lydgate's shorter poems. While extant scholarship on Shirley tends to narrowly focus on his biography or on the codicology of his manuscripts, this dissertation connects his life and works to larger discourses of literary history. While my research expands and challenges past scholarship on the audience of Shirley's manuscripts, I contend that Shirley played a much more extensive role in the development of English literary culture than has previously been acknowledged. Integrating manuscript studies and literary history, this project provides new insight into the profound transformations in the meanings of "literature," authorship, canonicity, and pre-print "publishing" in fifteenth-century England. I argue that Shirley played a new role in the development of ideas of authorship and the English literary canon; during an age when poetry regularly circulated anonymously, his anthologies, which specifically attribute poems to various authors, are radically author-centered and embody a marked shift from the "household books" or thematically grouped anthologies of courtly and religious verse which usually circulated in England in his life time. My research explores how Shirley's conception of these issues is embedded in the mise-en-page, or lay-out, of his manuscripts (including his prefaces, introductory headnotes, colophons, running titles and glosses), and was disseminated throughout the nascent English literary community as his manuscripts circulated in varied "reading circles" during his lifetime and were copied and used as exemplars after his death. Complete transcriptions of Shirley's headnotes, colophons, and running titles, many of which are unedited and unpublished, are appended.