Historia Brittonum and 'Saxon Annals': A case for convergence in the historiography of post-roman Britain

Analysis here of chapter 66 of 'Historia Brittonum' suggests that its chronology diverges less from that of Bede and 'Anglo-Saxon Chronicle' than previously believed. The author's own testimony demonstrates that he misunderstood the significance of Roman consuls. His belief that consuls, and not emperors, ruled Rome after 388 led him to delete twentyfour years from the reign of Valentinian III. This in turn shifted every date in chapter 66 back some two decades. But when this single error is corrected, 'Historia Brittonum's' chronology becomes much more consistent with that of other works of early Insular historiography. Most significant, this apparent convergence mandates a comprehensive re-examination of all the early written sources for post-Roman British history.