The Vexillation

[Flavivs Aetivs]

IIRC, the Vexillatio only applies to units in the field armies. Some of these units were raised from old Legionary cavalry detachments, giving them the name of "Equites Promoti" and were in the range of 120 men (even the Panopolis/Elephantine Papyrii support this in the analysis of the cavalry regiments of II Traiana and (I think it's) III Herculea).

Many of the Catafractarii and Clibanarii units may have been Alae, some may have even been Cohortes. They started being replaced by Cunei in the late 4th century, which are dominant on the Danube fronteir Limitanei. The Cuneus seems to have been the same as Arrian's Tarentiarchia, numbering 240 and 256 men, respectively, although we don't know if Symmachus' 240 Unnigardae were organized in a regular Roman formation or not.

I'm working on doing better estimates of the strength of the Notitia Dignitatum, but its a very confusing document. Most of my refining only shows that the cavalry contingent in the field armies is smaller than most people make it out to be: It's only about 3000 men in the Thracian Field army, compared to 24,000 infantry.

Ammianus does make several mentions of Legionary detachments and calling them Vexillations. A lot were mentioned in our former discussion on Late Roman unit Sizes (I think it's called just that. I stickied it in the Roman History forum.) I need to go through that again...

EDIT:

Columbia 7.188 - from AD320, giving a vexillatio of equites promoti of II Traiana 264 men.

[antiochus]

Evan wrote:
IIRC, the Vexillatio only applies to units in the field armies.

No, in the principate it is an official organisation. That is why the number of vexillations can be determined before a campaign begins. A commander, like Agricola can select a specific number of vexillations from his four legions that he thinks would be suitable for his forthcoming campaign. From the cavalry numbers, it works out the ratio of legionaries to auxiliary infantry at Mons Graupius was 1 to 1. Therefore, in round terms, Agricola had 19,000 men.

Evan wrote:
Many of the Catafractarii and Clibanarii units may have been Alae, some may have even been Cohortes. They started being replaced by Cunei in the late 4th century, which are dominant on the Danube fronteir Limitanei.

Ok, you are more knowledgeable on this than me. I called it an ala for having no better term. Do we know what two cunei would be called? Or three of four or five?

Evan wrote:
The Cuneus seems to have been the same as Arrian's Tarentiarchia, numbering 240 and 256 men, respectively, although we don't know if Symmachus' 240 Unnigardae were organized in a regular Roman formation or not.

What if I said the 240 Unnigardae were organised on Roman lines, would you believe me?

Evan wrote:
I'm working on doing better estimates of the strength of the Notitia Dignitatum, but its a very confusing document.

Amen to that. Coello in his thesis Unit Sizes in the Late Roman Army page 47 states: “The British sections of the Notitia record only five alae, 18 cohorts and five numeri which are clearly survivals from the third century.” I work this out to be 12,300 men.

Evan wrote:
Most of my refining only shows that the cavalry contingent in the field armies is smaller than most people make it out to be: It's only about 3000 men in the Thracian Field army, compared to 24,000 infantry.

That is a ratio of 8 infantry to one cavalry, which is in the Roman category.

Evan wrote:
Nathan Ross wrote:
Columbia 7.188 - from AD320, giving a vexillatio of equites promoti of II Traiana 264 men.

That number is a modern estimate Evan and I would not use it. If it is wrong, you are wrong. A wrong premise equals a wrong conclusion. Stick with the primary sources.

Evan wrote:
It's likely they operated the same way as the Schola Palatina - there were 7,000 Scholae but the Emperor's Guard only numbered 40 Candidati.

Do you have a reference for the 40 Candidati Evan?

[Nathan Ross]

ILS 4195 indicating ten cohorts I believe it just before the reforms of Diocletian, possibly five years earlier.

Maximian's Mauretanian campaign is usually dated to AD298-299. Diocletian and Maximian abdicated in AD305. Whatever military reforms were conducted under the tetrarchy were surely done sooner rather than later, to shore up a pre-existing situation.

ILS 8882 from Koptos in Egypt, dated A.D. 315-16, is the last reference to a legionary vexillation: men of legion III Gallica and I Illyricorum, together with a numerus of Emesene archers, under a praepositus. Most praepositi seem to have been centurions or protectores.

About cohorts - the last reference would probably be AE 1982, 258, from Otricoli: Val(erius) Iustin/us miles legionis s/ecund(a)e Italic(a)e Divite/nsium civis R(a)etus / militavit annis V / vixit an(n)is XXV co(ho)r(ti)/s VII...

This is usually dated to Constantine's march on Rome in AD312.

I have come to the conclusion, the vexillation of both infantry and cavalry was abolished due to the maths not working.

I would think that tactical and strategic considerations would have been more pressing!

[Flavivs Aetivs]

No, in the principate it is an official organisation. That is why the number of vexillations can be determined before a campaign begins. A commander, like Agricola can select a specific number of vexillations from his four legions that he thinks would be suitable for his forthcoming campaign. From the cavalry numbers, it works out the ratio of legionaries to auxiliary infantry at Mons Graupius was 1 to 1. Therefore, in round terms, Agricola had 19,000 men.

I was talking about the Notitia here.

Ok, you are more knowledgeable on this than me. I called it an ala for having no better term. Do we know what two cunei would be called? Or three of four or five?

Quinque Cunei?

What if I said the 240 Unnigardae were organised on Roman lines, would you believe me?

I highly suspect that it is, and I suspect that the Promoti Vexillationes were organized into 256 man units, and 264 would not be out of the question as that would be 256 men plus 8 officers.

Amen to that. Coello in his thesis Unit Sizes in the Late Roman Army page 47 states: “The British sections of the Notitia record only five alae, 18 cohorts and five numeri which are clearly survivals from the third century.” I work this out to be 12,300 men.

That depends, Zozimus and Ammianus both support an Ala of something like 640 men! (Ammianus says 700, Zozimus says 600, and both also say 360 with Julian.)

Interestingly enough, an Auxilia Palatina Arithmos (Numerus) if it comes out to 8 centuries totalling 640 men, including officers would number almost the same as Zozimus' 666 men.

The British Command is far larger than that... I get roughly 38,000 men from both commands combined (the Comes Britanniarum was likely created when Stilicho visited in 402 and transferred to Gaul under Constantine III in 405 though.)

That number is a modern estimate Evan and I would not use it. If it is wrong, you are wrong. A wrong premise equals a wrong conclusion. Stick with the primary sources.

I give the papyrii mention but note that it is based off modern and probably flawed estimates.

Do you have a reference for the 40 Candidati Evan?

It's just one of those things I know but don't remember where I learned it from. AFAIK it is right though.

[antiochus]

Nathan wrote:
This is usually dated to Constantine's march on Rome in AD312.

Thanks for the reference. This indicates to me the smaller cohort organisation was not abolished.

Evan wrote:
That depends, Zozimus and Ammianus both support an Ala of something like 640 men! (Ammianus says 700, Zozimus says 600, and both also say 360 with Julian.)

Besides Ammianus mentioning the 700 cavalry consisting of two turmae, and Zosimus terming cavalry a tagmata, am I to understand there is no evidence of what names were given to the various cavalry organisation (200 men, 240 men, 300 men, 360 men, 600 men, and 700 men)? A cavalry vexillation has to be taken from an official cavalry organisation larger in size than a vexillation. I really need to know if the term ala has been changed and what would a half ala and a quarter ala be called. If there is nothing besides a Cunie which you indicate amounts to 240 men, then that is what I will work with.

Evan wrote:
Interestingly enough, an Auxilia Palatina Arithmos (Numerus) if it comes out to 8 centuries totalling 640 men, including officers would number almost the same as Zozimus' 666 men.

I’m at present investigating an arithmoi as numbering 600 men consisting of two numeri of 300 men.

Evan wrote:
The British Command is far larger than that...

From my understanding Coello is only discussing half the auxiliaries.

[Nathan Ross]

Ammianus mentioning the 700 cavalry consisting of two turmae, and Zosimus terming cavalry a tagmata

Ammianus is writing in Latin, Zosimus in Greek; they could be referring to the same thing.

an arithmoi as numbering 600 men consisting of two numeri of 300 men.

Again, arithmos (singular) is Greek, numerus is Latin. The two words appear to refer to the same formation.

[Flavivs Aetivs]

Arithmos in a 5th Century Roman context is a Greek term for a Numerus, yes. My estimates say it numbered 640 men plus 19 officers, totalling 659 men.

I forgot Zozimus says Tagmata, not Ile. I need to fix that.

[antiochus]

Nathan wrote:
Again, arithmos (singular) is Greek, numerus is Latin. The two words appear to refer to the same formation.

Oh give me the republic anytime…it was all straightforward. So without having one idea of plural or singular, can two numeri each of 300 men be called a numerus?

Evan wrote:
Arithmos in a 5th Century Roman context is a Greek term for a Numerus, yes. My estimates say it numbered 640 men plus 19 officers, totalling 659 men.

Well you and I are on the same track. However, it’s 600 men for me without officers.

[Nathan Ross]

So without having one idea of plural or singular, can two numeri each of 300 men be called a numerus?

Not sure if I understand you!... numerus is singular, numeri plural.

Since numerus is a rather mutable term (meaning 'unit', essentially), I suppose it's not impossible that two smaller numeri could be combined to make a bigger numerus! The word seems to have been used for military units of varying sizes.

[Flavivs Aetivs]

But it also seems to have standardized in size by the time of the Notitia Dignitatum.

[Nathan Ross]

standardized in size by the time of the Notitia Dignitatum.

We might assume so - but do we know so? I'd also be wary of estimating unit size by subdividing larger figures in literary sources, as we don't know if all the individual units making up the total were an equal size or at full strength.

[antiochus]

Nathan wrote:
Since numerus is a rather mutable term (meaning 'unit', essentially), I suppose it's not impossible that two smaller numeri could be combined to make a bigger numerus! The word seems to have been used for military units of varying sizes.

Then two numeri each of 300 men forms a numerus of 600 men.

Evan wrote:
But it also seems to have standardized in size by the time of the Notitia Dignitatum.

I have found there is a complete standardisation of everything in the Roman system, including the Late Roman legion. Vegetius’ reference to four infantry and four cavalry being selected for guard duty belongs to the Late Roman legion. So if four men are taken from each century for guard duty, could four men from each century form a 300 man numeri? That would indicate the 300 men could have been taken from a total of 75 centuries.

The reference to those four infantry and four cavalry and the rest of the empirical data again confirms the size and organisation of the Late Roman legion adheres to the Pythagorean system. Diocletian took the number of infantry in the tribal system and separated it into three divisions. Same with the cavalry. Each division is then divisible by two.

My advice Evan is to stay with the standardisation theory. It is the Roman way.

[Renatus]

Then two numeri each of 300 men forms a numerus of 600 men.

I'm a bit dubious about this. The epigraphic evidence suggests that the term numerus was applied to specific units, so I am doubtful if two such units combined would still be considered as a single numerus. I think that I would need to see some evidence of that.

Vegetius’ reference to four infantry and four cavalry being selected for guard duty belongs to the Late Roman legion. So if four men are taken from each century for guard duty, could four men from each century form a 300 man numeri? That would indicate the 300 men could have been taken from a total of 75 centuries.

Vegetius speaks of four infantry and four cavalry being taken from each century, so eight men are taken, not four. Does this create a problem for your figures?

[antiochus]

Michael wrote:
Vegetius speaks of four infantry and four cavalry being taken from each century, so eight men are taken, not four. Does this create a problem for your figures?

There’s no problem whatsoever. The men taken from the centuries will form their own centuries. An 80 man century is divisible by eight.

[Renatus]

. . . could four men from each century form a 300 man numeri? That would indicate the 300 men could have been taken from a total of 75 centuries.

The men taken from the centuries will form their own centuries. An 80 man century is divisible by eight.

But 300 is not divisible by 80, or am I being particularly dense?