Harrison is here running two episodes, both the creation of Geoffrey of Monmouth but separated by about 150 fictional years, into one. Guithelinus, archbishop of London, went from Britain to Brittany to seek help there immediately after the end of Roman rule, whereas Archbishops Theonus of London and Tadioceus of York fled their dioceses to Wales in the late sixth century in order to escape the attacks of the African king Gormund - Historia regum Britanniae Books VI c.4, XI c.10.