And here Æðelfrið led his army to Chester, and there slew countless Welsh. And came about Augustinus's prophecy, that he said "If they do not have peace with us, they will die at the hands of the Saxons." There also were slain 200 priests who came there to pray for the Welsh army. Scrocmail was called their leader, and he escaped as one of fifty." In the "Brut y Brenhinedd" (), which is a collection of variant Middle Welsh versions of Geoffrey of Monmouth's Latin chronicle "Historia Regum Britanniae" ("History of the Kings of Britain"), the battle is called "Perllan Fangor" (). "Brut" proved especially influential in medieval Wales, where it was largely regarded as an accurate account of the early history of the Britons. It therefore suggests the battle may have taken place nearer to Bangor-on-Dee rather than Chester. Bede mentions the killings of British monks by the Anglo-Saxons. He wrote that the monks:   "resorted...to pray at the...battle...King Æthelfrith being informed [of this]...said, "If then they cry to their God against us, in truth, though they do not bear arms, yet they fight against us, because they oppose us by their prayers." He, therefore, commanded them to be attacked first ... About twelve hundred of those that came to pray are said to have been killed". This episode was also noted in the Annals of Ulster s.a. 612 (recte 613):   "Bellum Caire Legion ubi sancti occisi sunt" (The battle of Caer Legion, in which holy men were slain)  Bede thought this was divine retribution for the Welsh bishops refusing to join Augustine of Canterbury in proselytizing the Saxons. During the English Reformation scholars such as Matthew Parker frequently argued that Augustine himself had been complicit in the battle and the massacre, but this contention swiftly degenerated into a sectarian dispute. The argument relies on the 604 date for the battle found in the "Anglo-Saxon Chronicle" as well as the suggestion that a passage in Bede that specifically exculpates Augustine, which appears in the Latin but not in the early English translation of the text, was a later addition aimed at distancing the churchman from the violence he predicted. The usually accepted dates 615/16 for the battle mitigate this argument, as Augustine is believed to have died in 604.