Zodiac and Late Roman Army Organisation

[Robert Vermaat]

Hi Steven,

Mr Campbell wrote: It is usually assumed that the late legion was smaller than its imperial predecessor, so I don't think you'll find much support for a 7,200-man unit. (Just my opinion.)

In general I would agree with you, but it very much depends on the time and the place. As far as we can tell, the Roman army reform that began somewhere in the late 3rd c., continued for a number of decades. Since no-one thinks that the Emperor decreed that at some date, all units were to be split up, I think it perfectly acceptable that at some point between 280 and, say, 330 AD, we can find legions with a strength of 6-7000. Splits did occur in half-legions of 3000 each (depending on older limitanae or newly created comitatenses units), or into cohorts of about 500 each.

Nicasie (already mentioned earlier by Adrian) estimates the following Late Roman unit strengths:
scholae - 500
legiones (comitatenses) - 1000
legiones (limitanei) - up to 3000
auxilia palatinae - 800
infantry units (limitanei) - 300
cavalry units (limitanei) - 350

I’m advocating units of 1200 men

Your ideas are based on with sources?

How did you know my sources were the Anastasian Edict stones from Perge by Onur.

If this source is the base for that assumption, please let us know, because a) Onur did not yet publish that part of the inscription (as far as I know) and b) it’s fairly late when compared to other sources, which do not agree.
However, if it’s indeed the case, it could be an interesting development.

Adrian wrote: From Zosimus we know that Late Roman auxilia units were 1000 men strong, and I would think that the Legiones would have been larger, how much larger is open to much debate!
That’s what I suspected. There isn’t enough information.

There is more besides Zosimus, and it’s coming from all kinds of sources. It was Mommsen who first noticed that old style legions were probably broken up into 6 detachments of a 1000, each of these commanded by one of the 6 tribunes of the old unit. Only the legions of the limitanei were still commanded by praefecti. Only Nischer proposed that 'new' legions existed of two units of 500, drawn from every border legion, but his theory lacks evidence. However, the Beatty papyrus mentions detachments of 500 men. One vexillatio consisted of 1000 men from legio III Gallica and legio I Illyrica. Another, from legio II Traiana, consisted of two 500-men units. Two vexillationes of legio III Diocletiana numbered 1100. Best not think of the Roman army in modernisms – it was never as clear-cut as we are used to today.

Sean Manning wrote: That one seems really hard ... we don't have many descriptions of paper organization in the late empire.
Thanks, that is what I thought was the case. I feel better having it confirmed.

In fact we have more than we have for the earlier periods.

Some of the material I have been reading has been very frustrating and not helpful. So far I’ve read about units of 1000 men or 1200 men but no has given references.

. Again, try to find Nicasie, who wrote a phd about this subject, and is crammed with references. That how I use his book anyway:
Nicasie, Martijn (1997): Twilight of Empire, the Roman Army from the Reign of Diocletian until the Battle of Adrianople, (Thesis Publishers Amsterdam).

If you want to see numbers and sources, I’ve listed a number of them in my article: http://www.fectio.org.uk/articles/numbers.htm

Nathan Ross wrote: But I'm not sure whether you're actually trying to research the organisation of the army, or just searching for bits of evidence to map onto your theory about astronomy.
[..]
I’m after information on the organisation of the Roman army and at the same time trying to experiment how six units of 1200 men could be organised.

I’ve come across a lot of numbers, but never 1200 or 600. 300, 500, 800, 1000 and 1500 for infantry (Ammianus, mostly).

The old style alae numbered 500 and seem to have remained that way. The ala III Assyriorum was organized in old-style 11 turmae, giving it a possible strength of 350 (ChLA XVIII 660). Ammianus mentions that the cataphracti defeated at Strasbourg were 600 strong, which is echoed by Johannes Lydus who says that alae were that number, and turmae 300 but also 500 (De Mag. I.46). Ammianus also mentions two turmae at Amida numbering 700 together (XVIII.8.2). Procopius has various sizes, between 200 and 800 strong (800: Bella VI.5.1, VI.7.25-6). Some units are larger, between 1000 and 1500, but it is unclear if these are units grouped together, or maybe allied forces (1500: Bella V.27.22-3 and VII.34.42). Maurikios mentions cavalry units should be between 300 and 400, but in any case not less than 200 and not above 400; if understrength, they should be combined.

the NT gives the names of units of exculcatores.

I adhere to the opinion that a lot of unit names in the Notitia are NOT to be taken literally. In many cases we just know that this is the case (some tribal names simply refer to non-existing tribes), and in some cases we have a very strong indication. The Exculcatores are, together with for instance the superventores, exploratores, and praeventores, were probably originally created from a much smaller group of specialists or a vexillation, and retained the name but not the specialism.

Of the 7200 men, 3600 are iuniores and 3600 are seniores. These 3600 men are then vertically organised into three units of 1200 men made up of different troop types, possibly one type is exculatores, the second lanciarii and to the third, I have no idea, but possibly lanciarii again. In this manner the army has a vertical organisation and horizontal organisation each numbering 1200 men. I’m basing my research on units of 1000 men are pre 400 AD and units of 1200 men are post 400 AD.

I have never, EVER, come across a structure such as this hypothesis, in any Late Roman unit. IF this would have been the case, we would at some point have found a description of a soldier being either this or that, serving in the same unit. We haven’t.