place 12 years from the reign of Vortigern. It is not clear how these various traditions about Ambrosius relate to each other, or whether they come from the same tradition; it is very possible that these references are to different men with the same name. Frank D. Reno points out that the works call all these men "Ambrosius"/"Emrys". The cognomen "Aurelianus" is never used. The Historia Brittonum dates the battle of Guoloph to "the twelfth year of Vortigern", by which the year 437 seems to be meant. This is perhaps a generation before the battle that Gildas may imply was commanded by Ambrosius Aurelianus. The text never identifies who Ambrosius's father is, just gives his title as a Roman consul. When an adolescent Ambrosius speaks of his father, there is no suggestion that this father is deceased. The boy is not identified as an orphan. The exact age of Ambrosius is not given in his one encounter with Vortigern. Frank D. Reno suggests that he might be as young as 13 years old, barely a teenager. It is impossible to know to what degree Ambrosius actually wielded political power, and over what area. Ambrosius and Vortigern are shown as being in conflict in the Historia Brittonum, and some historians have suspected that this preserves a historical core of the existence of two parties in opposition to one another, one headed by Ambrosius and the other by Vortigern. J. N. L. Myres built upon this suspicion and speculated that belief in Pelagianism reflected an actively provincial outlook in Britain and that Vortigern represented the Pelagian party, while Ambrosius led the Catholic one. Subsequent historians accepted Myres's speculation as fact, creating a narrative of events in 5th century Britain with various degrees of elaborate detail. Yet a simpler alternative interpretation of the conflict between these two figures is that the Historia Brittonum is preserving traditions hostile to the purported descendants of Vortigern, who at this time were a ruling house in Powys. This interpretation is supported by the negative character of all of the stories retold about Vortigern in the Historia Brittonum, which include his alleged practice of incest. The identity of Ambrosius's last mentioned enemy, Vitalinus, is somewhat obscure. Various manuscripts of the Historia and translations also render his name as "Guitolin," "Guitolini," and "Guitholini." He is mentioned in chapter 49 as one of four sons of Gloiu and co-founder of