Late Roman Legion size based on the Perge Inscription

[Nathan Ross]

Army rosters are useless if we do not have the exact organisation of a Roman legion or any unit for that matter to compare with.

The Perge tablets are not an army roster in the sense of a temporary roll-call, like the Dura reports or the ones from Vindolanda. They show us the official total numbers of a late 5th-century legion (or 'numerus legionem') at full strength. This is the hardest of hard evidence, literally carved into stone!

The trouble is, of course, that the inscription is fragmentary, hard to decipher, and there's a lot that we don't know about it. Is the unit described a normal one, or exceptional? For how long did this organisation persist? (for the numbers to need recording in such detail, we might assume there was something unusual or novel about them...)

This underlines the difficulties of using ancient texts, or ancient evidence of any sort. None of it can be regarded as a clear window into the past, all of it requires interpretation, and none of those interpretations are going to be exact or perfect.

 8 units x 1,104 soldiers = 8,832 soldiers. Now if I doubled the eight units to 16 units and then divided the 8,832 soldiers by 16 units, this produces 16 units each of 552 soldiers. But there’s more! At this stage, if I double the 552 soldiers this makes 1,104 soldiers, which brings us right back to Macarius’ figure of 1,104 soldiers stationed at Melitene. Can someone tell me where the maths is wrong?

You have shown that 1104 can be divided by 8 and 16. But 9000 cannot, and nor can 7700, 1300. You can assume that these numbers are 'rounded' if you like, but if your thesis depends on exact number concordances you need to show that working, rather than rounding numbers up or down to make them fit.

Pacatus writes that “the plain was bristling with troops: cavalry sent out to the wings, light troops placed in front of the standards, cohorts arranged by maniples, legions arrayed in squares, moving their columns forward at a quick pace, occupied the whole field as far as the eye could see.”

Pacatus has earlier told us that Theodosius's army at the Frigidus was recruited from large numbers of Goths, Huns and Alans - but then has them formed into cohorts and maniples, throwing pila and fighting with the gladius! His battle description is a classicising set-piece, written 'in the grand style', as Ammianus recommends, and like both Ammianus and Claudian he uses traditional language drawn from the great writers of the past. This is totally normal and accepted practice for poets and panegryrists of the period, and we should not be bamboozled by it!

[Edit - however, I don't think this is always the case; when Claudian writes of Stilicho ordering 'a legion' to support the routed Alanic cavalry on his flank at Pollentia, ('instructa Stilicho legione secutus subsidiis peditum pugnam instaurasset equestrem'), I think he was referring to a specific event; in this case the last known reference to Roman regular troops fighting in a field battle!]

So, how did I manage to get Vegetius and the 1,104 soldiers to work? Well, first, I never listened to the nay sayers on this forum

I'm sure that I am one of those nay-sayers, so pay no attention if you like! But to be exact, Vegetius has 1105 infantry in his first cohort, not 1104. The similarity is interesting nonetheless.

Also, as I've mentioned before, Macarius was not a historian but one of the martyrs in the story, and the 1104 men were not a complete unit but only those members of the unit at Melitene who confessed Christianity and were executed.

the 280-strong regiment I suggested (5 clerici et deputati, 50 Veredarii, 225 Veredarii Alii) can still be divided into 5 56-man Turmae, which is enough for 1 to support each 320-man cohort.

The problem is that the clerici and deputati are probably not the same - they may have been unit priests and medical orderlies, as I think Onur suggests? - and they were not on the army payroll, as they drew no annonae. Putting one supernumerary 'civilian' in the ranks of each turma would seem a bit superfluous, surely?

it could be that a cavalry unit was added to at least some of the Legions (perhaps those whose Equites had not been used by Gallienus to create new Promoti units) to give them some added striking power and improved communications and intelligence-gathering capabilities to offset their smaller size?

I've wondered elsewhere whether this Perge numerus may have been specially constituted as a combined infantry and (light?) cavalry unit, for a particular purpose related to the Isaurian situation; a sort of counter-insurgency force, maybe. However, carving the unit organisation onto a huge tablet suggests they were intended to remain there, and keep that same formation, for some time!

(incidentally, could you edit down the posts you quote in your replies to the specific bits to which you are replying? These threads get awfully long and repetitive otherwise!)