THE TWO ARTHURIAN THEORIES AND THE PROBLEM OF NAME TRANSMISSION

Artistic Rendering of Ribchester Roman Fort

If, however, we must settle for ARMENIOS as the most reasonable rendering of ARM[...]S, then Castus was not in Britain when the Sarmatians were there.  We would look not to the name Arthur cropping up at Dark Age Ribchester, but instead at Dinas Emrys in the vicinity of Segontium in NW Wales, whose garrison had been sent to Castus' Dalmatia.  Welsh tradition puts Uther's relatives at Dinas Emrys (= Caer Dathal, a certain identification).  The Segontium connection is, however, extremely weak.  We would have to allow for one of the retired unit members returning home from Dalmatia and then, for some reason, having brought the Artorius name back with him.  Why he would have done that is the main question, for even if he encountered the LAC inscription or had been told about LAC leading British troops to Armenia centuries ago, we must ask the next logical question: of what possible importance would such a remote figure have been to him? On the other hand, we might well expect the Sarmatian veterans at Ribchester to have remembered the Roman officer who took 1500 Sarmatian cavalrymen from Britain to Rome to demand the execution of the Praetorian Prefect Perennis.  

Excerpted from https://mistshadows.blogspot.com/2022/10/a-tale-of-two-arthurs-or-tenuous-nature.html

As I've remarked before, Artorius could have been a more or less commonly occurring name in sub-Roman Britain.  While I think this is unlikely, it is still a possibility.  If it's the case, then we cannot predicate any of our Dark Age Arthurs on some inherited name stemming, ultimately, from a 2nd century Roman officer stationed at York.  It might well be that a thoroughly Celtic 'bear-' name was simply replaced by Artorius as a decknamen because Artorius resembled the said name and was distinctily Latin.

But if, as I suspect, the origin of the name Arthur is to be sought specifically in the Artorius of L. Artorius Castus, then we must ask what would be the most probable way that name could have been preserved and passed down among the generations.

Discounting the nebulous Segontium garrison's tie to LAC's Dalmatia, and the hugely attractive Ribchester connection, we are left with York (with a Dalmatian unit stationed nearby, possibly in that fort's vicus) and the Hadrian Wall fort of Carvoran (whose garrison was Dalmatian in the later period).  Yet we have no evidence in the Welsh tradition for Arthur or his father being at either of these places.  Granted, there is a horribly corrupt reference to Arthur being the son of Eliffer of York; this must be abandoned. And while Carvoran is close to both Camboglanna and Aballava/Avalana on the Wall, we again cannot find any way to put Arthur or his father at Carvoran.  I would add that all the top Roman military historians I have talked to about this are more than a little uneasy with the idea of Artorius being preserved among Dalmatian units that, over the centuries, had long ceased to be Dalmatian in anything but title.  

What this all means is that the best avenue for the transmission of the name Arthur is to be found at Ribchester, with its Sarmatian veterans.

Note that I am not - and nor will I ever be - willing to accept the absurd notion that Castus was the Arthur and that, somehow (apparently through undemonstrable folklore processes) we are to regard the various Dark Age Arthurs not as historical figures, but as temporally dislocated manifestations of the 2nd century officer.