Ambrosius Aurelianus (; Anglicised as Ambrose Aurelian and called Aurelius Ambrosius in the Historia Regum Britanniae and elsewhere) was a war leader of the Romano-British who won an important battle against the Anglo-Saxons in the 5th century, according to Gildas. He also appeared independently in the legends of the Britons, beginning with the 9th-century Historia Brittonum. Eventually, he was transformed by Geoffrey of Monmouth into the uncle of King Arthur, the brother of Arthur's father Uther Pendragon, as a ruler who precedes and predeceases them both. He also appears as a young prophet who meets the tyrant Vortigern; in this guise, he was later transformed into the wizard Merlin.
According to Gildas Ambrosius Aurelianus is one of the few people whom Gildas identifies by name in his sermon De Excidio et Conquestu Britanniae, and the only one named from the 5th century. De Excidio is considered the oldest extant British document about the so-called Arthurian period of Sub-Roman Britain.Reno (1996), p. 263–282 Following the destructive assault of the Saxons, the survivors gather together under the leadership of Ambrosius, who is described as:
Ambrosius was possibly of high birth and very likely a Christian: Gildas says that he won his battles "with God's help". Ambrosius's parents were slain by the Saxons and he was amongst the few survivors of their initial invasion.
According to Gildas, Ambrosius organised the survivors into an armed force and achieved the first military victory over the Saxon invaders. However, this victory was not decisive: "Sometimes the Saxons and sometimes the citizens [meaning the Romano-British inhabitants] were victorious." Due to Gildas's description of him, Ambrosius is one of the figures called the Last of the Romans.Venning (2013), Ambrosius Aurelianus, unnumbered pages
Scholarship questions Two points in Gildas's description have attracted much scholarly commentary. The first is what Gildas meant by saying Ambrosius' family "had worn the purple". Roman emperors and male Patricians wore clothes with a purple band to denote their class so the reference to purple may be to an aristocratic heritage. Roman military tribunes (tribuni militum), senior officers in Roman legions, wore a similar purple band so the reference may be to a family background of military leadership. The tradition was old, as the togas and pallia of already ancient senators and tribunes were trimmed with the purple band. In the church, "the purple" is a euphemism for blood and therefore "wearing the purple" may be a reference to martyrdomCraughwell (2008), pp. 106–112 or a bishop's robe. In addition, in the later Roman Empire both Roman consuls and governors of consular rank also wore clothes with a purple fringe. The Notitia Dignitatum, a Roman catalogue of official posts, lists four or five provincial governors in Roman Britain and two of them were of consular rank. One was the governor of Maxima Caesariensis and the other that of Valentia. The parent who wore the purple may well have been one of these governors, whose names were not recorded.Ashley (2005), De Excidio, unnumbered pages
It has been suggested by historian Alex Woolf that Ambrosius may have been related to the 5th-century Romano-British usurpers Marcus or Gratian – Woolf expresses a preference based on nomenclature for Marcus. Frank D. Reno, an Arthurian scholar, has instead argued that the name "Aurelianus" indicates the descent of Ambrosius from the Illyrian Roman emperor Aurelian (reigned 270–275). Aurelian's military campaigns included the conquest of the Gallic Empire. N. J. Higham suggests that Ambrosius may have been distantly related to imperial families of the late Roman Empire, such as the Theodosian dynasty. Branches of this particular dynasty were known to be active in western Roman provinces like Hispania.Higham (1994), p. 35–66
Mike Ashley instead focuses on the name "Ambrosius" and its possible connection to Saint Ambrosius, a fourth-century Bishop of Milan, who also served as consular governor in areas of Roman Italy. The father of the Bishop is sometimes claimed to be a fourth century Praetorian prefect of Gaul named Aurelius Ambrosius, whose areas included Britain, though some modern scholars doubt that Saint Ambrosius was related to this man (instead identifying his father with an official named Uranius mentioned in an extract from the Theodosian Code).Barnes, T. D., "The Election of Ambrose of Milan", in: Johan Leemans (ed), Episcopal Elections in Late Antiquity, de Gruyter, 2011, pp 39–60.Mazzarino, S. "Il padre di Ambrogio", Helikon 13–14, 1973–1974, 111–117.Mazzarino, S., "Storia sociale del vescovo Ambrogio", Problemi e ricerche di storia antica 4, Rome 1989, 79–81. Ashley suggests that Ambrosius Aurelianus was related to the two Aurelii Ambrosii. Tim Venning points out that the name "Aurelianus" could be the result of a Roman adoption. When a boy was adopted into a new gens (clan), he received the family names of his new family but was often additionally called by a cognomen indicating his descent from his original family. The additional cognomen often had the form "-anus". When Gaius Octavius from gens Octavia was adopted by his uncle Gaius Julius Caesar, he was often distinguished from his adoptive father by the addition "Octavianus". In this case, Ambrosius may have been a member of gens Aurelia who was adopted by another gens/family.
The second question is the meaning of the word avita: Gildas could have meant "ancestors", or intended it to mean more specifically "grandfather" – thus indicating Ambrosius lived about a generation before the Battle of Badon. Lack of information prevents sure answers to these questions.
Gildas's motives N. J. Higham, author of a book on Gildas and the literary tropes that he used, has suggested that Gildas may have had considerable motive for drawing attention to Ambrosius. He was not attempting to write a historical biography of the man, according to Higham, but setting him as an example to his contemporaries. It was essential to the philosophy of Gildas that Briton leaders who achieved victory over the barbarians were only able to do so because of divine aid. And only those who had superior Christian virtues were deserving of this aid. Ambrosius Aurelianus was apparently known for at least one such victory over the barbarians. To fit him into his worldview, Gildas was almost required to feature the former warrior as a man of exceptional virtues and obedience to God. He was made to fit Gildas's version of a model leader.
Higham also suggests that the Roman lineage of Ambrosius was highlighted for a reason. Gildas was apparently intentionally connecting him with the legitimate authority and military virtues of the Romans. He was also contrasting him with the subsequent Briton rulers whose reigns lacked in such legitimacy.
Identifying historical figures Gildas is a primary source for the Battle of Badon, yet he never mentions the names of the combatants. It is not known if Ambrosius Aurelianus or his successors took part in the battle. The names of the Saxon leaders in the battle are not recorded.
The identities of Ambrosius's descendants are unknown, since Gildas never identifies them by name. It is assumed that they were Gildas's contemporaries and known to the author. Higham suggests that they were prominent figures of the time. Their lineage and identities were probably sufficiently familiar to his intended audience that they did not have to be named. The work portrays Ambrosius's descendants as inferior to their ancestor as part of his criticism on rulers of his time, according to Higham. Those criticised were likely aware that the vitriol was intended for them, but probably would not challenge a work offering such a glowing report of their illustrious ancestor.
Mike Ashley suggests that the descendants of Ambrosius could include other people named by Gildas. He favours the inclusion in this category of one Aurelius Caninus ("Aurelius the dog-like"), whom Gildas accuses of parricide, fornication, adultery, and warmongering. His name "Aurelius" suggests Romano-British descent. The insulting nickname "Caninus" was probably invented by Gildas himself, who similarly insults other contemporary rulers. Due to the name used by Gildas, there are theories that this ruler was actually named Conan/Cynan/Kenan. Some identify him with Cynan Garwyn, a 6th-century King of Powys, though it is uncertain if he was a contemporary of Gildas or lived one or two generations following him. Another theory is that this ruler did not reign in Britain but in Brittany. Caninus, in this view, might be Conomor ("Great Dog"). Conomor is considered a likelier contemporary of Gildas. Conomor was likely from Domnonée, an area of Brittany controlled by British immigrants from Dumnonia. He might be remembered in British legend as Mark of Cornwall.
Gildas primarily describes the Saxons as barbarian raiders; their invasions involved a slow and difficult process of military conquest. By AD 500, possibly the time described by Gildas, Anglo-Saxons controlled the Isle of Wight, Kent, Lincolnshire, Norfolk, Suffolk, and coastal areas of Northumberland and Yorkshire. The rest of the former Roman Britain was still under the control of the local Britons or remnants of the Roman provincial administration. Gildas also mentions depopulation of cities and this probably reflects historical facts. Londinium, once a major city, was completely abandoned during the 5th century.
According to Bede Bede follows Gildas's account of Ambrosius in his Ecclesiastical History of the English People, but in his Chronica Majora he dates Ambrosius's victory to the reign of the Emperor Zeno (474–491).
Bede's treatment of the 5th century history of Great Britain is not particularly valuable as a source. Until about the year 418, Bede could choose between several historical sources and often followed the writings of Orosius. Following the end of Orosius's history, Bede apparently lacked other available sources and relied extensively on Gildas. Entries from this period tend to be close paraphrases of Gildas's account with mostly stylistic changes. Bede's account of Ambrosius Aurelianus has been translated as following:
Bede does not mention the descendants of Ambrosius Aurelianus, nor their supposed degeneracy.
According to Nennius The Historia Brittonum, attributed to Nennius, preserves several snippets of lore about Ambrosius. Despite the traditional attribution, the authorship of the work and the period of its writing are open questions for modern historians. There are several extant manuscript versions of the work, varying in details. The most important ones have been dated to between the 9th and the 11th century. Some modern scholars think it unlikely that the work was composed by a single writer or compiler, suggesting that it may have taken centuries to reach its final form, though this theory is not conclusive.
In Chapter 31, we are told that Vortigern ruled in fear of Ambrosius. This is the first mention of Ambrosius in the work. According to Frank D. Reno, this would indicate that Ambrosius's influence was formidable, since Vortigern considered him more of a threat than northern invaders and attempts to restore Roman rule in Britain. The chapter relates events following the end of Roman rule in Britain and preceding Vortigern's alliance with the Saxons.