Constans and older brother of Uther Pendragon. Ambrosius and Uther are supposedly raised by their adoptive maternal grandfather Guthelinus/Vitalinus. It is not explicitly covered in Geoffrey's narrative, but this genealogy makes Constantine and his children descendants of Conan Meriadoc, legendary founder of the line of Kings of Brittany. Conan is also featured in the Historia Regum Britanniae, where he is appointed king by Roman emperor Magnus Maximus (reigned 383–388). Constantine's reign is placed by Geoffrey as following the Groans of the Britons mentioned by Gildas. Constantine is reported killed by a Pict and his reign is followed by a brief succession crisis. Candidates for the throne included all three sons of Constantine, but there were problems for their eventual rise to the throne. Constans was a monk, and Ambrosius and Uther were underage and still in their cradle. The crisis is resolved when Vortigern places Constans on the throne, and then serves as his chief adviser and power behind the throne. When Constans is killed by the Picts serving as bodyguards of Vortigern, Vortigern feigns anguish and has the killers executed. Ambrosius is still underage and Vortigern rises to the throne. The chronology offered by Geoffrey for the early life of Ambrosius contradicts Gildas and Nennius, and is also internally inconsistent. The Groans of the Britons involves an appeal by the Britons to Roman consul "Agitius". This person has been identified with Flavius Aetius (d. 454), magister militum ("master of soldiers") of the Western Roman Empire and consul of the year 446. The Groans are generally dated to the 440s and 450s, preceding the death of Aetius. If Geoffrey's Constantine rose to the throne immediately following the Groans, this would place his reign in this period. Geoffrey gives a 10-year reign for Constantine and his marriage lasts just as long. However the eldest son Constans is clearly older than 10 years by the time his father dies. He is already an adult candidate of the throne and has had time to follow a monastic career. Even assuming there is a time gap between the death of Constantine and the adulthood of Constans, his younger brothers have not aged at all in the narrative. Geoffrey's narrative has an underage Ambrosius, if not a literal infant, in the 460s. Accounts deriving from Gildas and Nennius place Ambrosius in the prime of his life in the same decade. Most telling is that Geoffrey