The Castus InscriptionLucius Artorius Castus was a Roman officer who lived in the late second century. When his military caraer and exploits are compared with those of Arthur there is some similarity. The two known inscriptions that detail the career of Lucius Artorius Castus place him firmly in Britain as a soldier who at one point in his career held the title "dux". While Arthur's title dux was eventually supplanted by rex ("king"), dux was clearly his original rank, and the development from dux to rex follows a direct line of transmission.
Lucius Artorius Castus does not mirror every detail of the Arthurian legends, however the parallels between King Arthur and Lucius Artorius Castus are striking across a range of details, both large and small.
Lucius Artorius Castus lived at a time that was perhaps earlier with the time span of the Arthurian legends.
Lucius Artorius Castus http://gorddcymru.org/twilight/camelot/infopedia/a/artoriuscastus_lucius.htmhttp://gorddcymru.org/twilight/camelot/infopedia/a/artoriuscastus_lucius.htm
Considered by some scholars to be one of the verified individuals whose exploits were incorporated into the legend of King Arthur. Used as the ancestor and progenitor of the Arthur of legend in the 2004 film "King Arthur".
"Lucius" is the praenomen, equivalent to a first name. Artorius is the nomen, and is important in that it describes the "gens," or family name. "Castus" (morally pure or clean) is a cognomen or a kind of personal or nickname. Sometimes it is titular or awarded, such as "Africanus" for winning a battle in Africa. It was quite important to describe the character as unique, such as saying "the Elder" or "the Fat".
A brief concentrated history of L. Artorius Castus pulled from info from Linda Malcor. 'Artorius was an equestrian rank Roman who, for some reason (perhaps hard economic times or he was a younger son with no chance of inheriting) resigned his rank and entered the Roman army as a centurion. He initially served in Syria, getting out just before war erupted by transferring to a legion stationed in Judea. He was then posted to a legion on the Danube, which was sent back to the Middle East because of the trouble there. When the trouble subsided, his legion returned to the Danube region, but at a site closer to where the Romans were fighting the Sarmatians. He made Primus Pilum, and, with that post, regained his equestrian rank and earned the right to retire. However, he stayed in the army, continuing to follow the traditional path for an equestrian officer. There is then a gap in his career of three to four years. His next known posting was as Praepositus (the naval equivalent of a tribune) in the Misenium Fleet, in charge of shipping supplies from Britain and the Mediterranean to Marcus Aurelius, who was still fighting in the Danube region. He was next posted in Britain as a Prefect in charge of an ala of numeri (some researchers claim as the Prefect of the Camp for the Sixth Victrix which is unlikely as such a position was a civilian post). Britain exploded with trouble along Hadrian's Wall during this timeframe. Picts destroyed the equivalent of at least two legions and the troops at Eboracum tried to make one of their commanders Emperor. During this chaos, many of the officers were executed or demoted and transferred to unsavory posts at the other extreme of the Empire. The only area where there wasn't trouble at this time was around Bremetennacum. The region stayed at peace and supplied loyal troops to the effort to defend Hadrian's Wall. At this time, a deputation of "javelin-men" from Britain traveled to Rome to warn Commodus of a pending assassination attempt. The only person who was in a position to send 1500 men anywhere was the commander at Bremetennacum. I think Artorius sent the warning. This curried favor with Commodus and when, soon after, someone was needed to put down an uprising in Armorica that the local legions were failing to handle, Artorius was appointed dux and sent to take care of the problem (ex-soldiers marauding around the countryside). He put down the uprising, returned his troops to Britain, and was rewarded for exemplary service by being appointed Governor of Liburnia (directly north of the region where Cassius Dio's father was serving as Governor). Artorius had acquired a wife (probably about the time he posted to Britain) and had several children. While he was serving as governor, he built a tomb for himself and his family, and presumably retired to a nearby villa. He seems to have had several daughters and possibly two sons (There are two Artorii with family names from L. Artorius Castus' branch who are killed while serving in the legions at this time.). The family did not continue to live in the region after his death, so the daughters likely married elsewhere and the sons were killed, causing the branch to die out.'
Castus has two inscriptions, carved in stone, that date to the 190s, that name him as the defender of western Britain and of the forts on Hadrian's Wall that show up in the Arthurian tradition and that detail the Armorican invasion.