The evolution of the Fenian tradition of story and song, traced over 1,400 years Stories about Fionn macCumhaill (also known as Finn McCool) and his roving warrior band, the Fianna, have engaged audiences for more than a millennium. Fionn and the Fianna—Gaeldom’s defenders during a legendary third-century golden age—are the heroes of the most prolific body of narrative in the Gaelic tradition, spanning 1,400 years of oral and written transmission, from the earliest extant records to the present day. In this book, Natasha Sumner traces these stories across the centuries and throughout the Gaelic world, examining the fates of Fionn and the Fianna and investigating the persistent popularity of these tales. Sumner describes the development of the Fenian tradition from early seventh-century texts through the medieval and early modern creation of its greatest literary achievements; the controversy stirred by James Macpherson’s adaptation of Fenian characters and plots in his popular eighteenth-century epic, Ossian; and the Fianna’s place in the modern Irish and Scottish nations, beginning with the Celtic Revival in the 1860s. Part (pseudo) historical fiction, part (proto) fantasy, these stories project perceptions of a bygone Gaelic heroic age through the lens of their contemporary realities. The Fenian tradition, Sumner argues, provides ample space for imaginative engagement with the narrative past, the historical present, and the aspirational future.