Chapter Five explores the transformation of early medieval origin material in historical chronicles written by nationalist authors in the early modern period. These antiquarians included the same origin legends that we find in our sources from the early medieval period in their later chronicles, yet they were using them in very different ways. While the origin narratives of the early medieval period were used to form cohesive histories of the insular region as a whole, early modern chronicles used this origin material to shift away from holistic insular narratives and towards a divisive nationalism. Chapter Five focuses on four representative samples from the voluminous corpus of late medieval and early modern historical works: John of Fordun’s Chronica gentis Scotorum (1385), later continued by Walter Bower as the Scotichronicon (1447); Holinshed’s Chronicles (first edition 1577; second edition 1587); William Camden’s Britannia (first edition 1586); and Seathrún Céitinn / Geoffrey Keating’s Foras Feasa ar Éirinn (completed 1634). This final chapter reveals how early medieval origin material was put to new uses during the early modern period as part of a shift towards a divisive nationalism from what had been an encyclopaedic approach to the history of the insular region as a whole.