How does a written literature come into being within an oral culture, and how does such a literature achieve and maintain its authority? Joseph Falaky Nagy addresses those issues in his wide-ranging reading of the medieval literature of Ireland, from the writings of St. Patrick to the epic tales about the warrior Cu Chulainn. These texts, written in both Latin and Irish, constitute an adventurous and productive experiment in staging confrontations between the written and the spoken, the Christian and the pagan.