Vegetius\' description of a Roman Legion

[JeffF]

It seems that the latest scholarly opinion is that the legion as Vegetius describes it never existed; that the lack of any corroboration by any other ancient author and the fact that the archaeological evidence of the period shows that barracks in fortresses maintained the room layout for the 80 man centuries of the early imperial period.

I'm not sure that logic necessarily applies. In my own experience in the US Army it seems to me that some future historian might easily dismiss one of the many evolutions of the organization of US Army divisions as fantasy, particularly the Pentomic Division which was the most drastic change in organization we ever adopted. When it comes to barracks some future archaeologist excavating barracks of the early 2000s would have completely erroneous conclusions due to the fact that we don't even house our troops by unit anymore.

I find it hard to believe that Vegetius could make such detailed conclusions from a misunderstanding of the information he had available to him.

I would like to read other opinions.

His description is below.

"The legion should consist of ten cohorts, the first of which exceeds the others both in number and quality of its soldiers, who are selected to serve in it as men of some family and education. This cohort has the care of the eagle, the chief ensign in the Roman armies and the standard of the whole legion, as well as of the images of the emperors which are always considered as sacred. It consists of eleven hundred and five foot and one hundred and thirty-two horse cuirassiers, and is distinguished by the name of the Millarian Cohort. It is the head of the legion and is always first formed on the right of the first line when the legion draws up in order of battle.
The second cohort contains five hundred and fifty-five foot and sixty-six horse, and is called the Quingentarian Cohort. The third is composed of five hundred and fiftyfive foot and sixty-six horse, generally chosen men, on account of its situation in the center of the first line. The fourth consists of the same number of five hundred and fifty-five foot and sixty-six horse. The fifth has likewise five hundred and fifty-five foot and sixty-six horse, which should be some of the best men, being posted on the left flank as the first cohort is on the right. These five cohorts compose the first line.
The sixth includes five hundred and fifty-five foot and sixty-six horse, which should be the flower of the young soldiers as it draws up in the rear of the eagle and the images of the emperors, and on the right of the second line. The seventh contains five hundred and fifty-five foot and sixty-six horse. The eighth is composed of five hundred and fifty-five foot and sixty-six horse, all selected troops, as it occupies the center of the second line. The ninth has five hundred and fifty-five foot and sixty-six horse. The tenth consists of the same number of five hundred and fifty-five foot and sixty-six horse and requires good men, as it closes the left flank of the second line. These ten cohorts form the complete legions, consisting in the whole of six thousand one hundred foot and seven hundred and twenty-six horses."

[M. Demetrius]

That's an interesting description, certainly. Can you post the location of that passage: in which book?

[Sean Manning]

If you read Vegetius, its pretty clear that he made some mistakes (eg. he thinks velites were cavalry; Veg. 3.23 "Velites autem erant iuuenes leui armatura et corpore alacri, qui ex equis optime missibilia dirigebant") and didn't understand that the Roman army had changed drastically over time (or at least minimized this to support his rhetorical image of one good old way and one bad modern way). The way he used sources from Cato the Elder to Emperor Hadrian without hinting at problems attests to that! So while his legion could be an accurate rendition of an organization we don't know about, it would be hard to prove, and even harder to assign it a particular date.

[JeffF]

the passage comes from Book II

If memory serves Gallienus consolidated the cavalry units of the legions into separate bodies for use as strategic or operational reserves. Is Vegetius the only source for the existence of large cavalry units within legions? It seems to me the relatively insignificant 120 man cavalrymen of the classic imperial legions would have been worthwhile to consolidate, it would take the detachments of four legions to create an alae of the same size as the quingenary auxilia alae.

As for Vegetius's mistakes I haven't read a history book without them so I wouldn't throw out his legion organization for that alone.

[M. Demetrius]

I wonder what the decision tree looks like for deciding "here Vegetius is totally correct/here he is entirely speculative". Same applies to Trajan's Column, Adamklissi metopes, Herodotus and other sources. It can't all be tied to the archeological record, as thing like tactics and organization would scarcely be represented by foundations of buildings and escavatory finds. Just wondering as always.

[Robert Vermaat]

If memory serves Gallienus consolidated the cavalry units of the legions into separate bodies for use as strategic or operational reserves.

No, that's a theory, based on some observations, but there is no proof that Gallienus did this. There is even evidence to a contrary view. Perhaps Gallienus was the one who created a single body from the legionary cavalry units (as perhaps other units were created from other sources, such as the governor's bodyguards), but it may have been some time until a standing reserve was created. We just don't know for sure.

[Sean Manning]

I wonder what the decision tree looks like for deciding "here Vegetius is totally correct/here he is entirely speculative". Same applies to Trajan's Column, Adamklissi metopes, Herodotus and other sources. It can't all be tied to the archeological record, as thing like tactics and organization would scarcely be represented by foundations of buildings and escavatory finds. Just wondering as always.

Just brainstorming but:

How much evidence do we have (more evidence -> a higher level of credence is possible if the evidence mostly agrees)
What does other evidence say?
Why did our source say this? Were they an eyewitness? Talked to an eyewitness? Read it- where? Hearsay? Didn't believe it at all but was trying for rhetorical effect?
Does this source describe something which did happen, or say it should happen? Eg. we know that a lot of imperial edicts were ignored after a decade or two; or trying to study the late Roman economy based on the Edict of Maximum Prices.
What hypotheses would produce the evidence we have? Which are simplest?

One source isn't worth much although it can give rise to interesting speculation.

[Robert Vermaat]

How much evidence do we have (more evidence -> a higher level of credence is possible if the evidence mostly agrees)
What does other evidence say?
Why did our source say this? Were they an eyewitness? Talked to an eyewitness? Read it- where? Hearsay? Didn't believe it at all but was trying for rhetorical effect?

Most of these questions are impossible to be answered for any source in Antiquity.
But one can compare:
Vegetius is the only source afaik who mentions a contubernium of 10 men, while all sources before and after him mention just 8.
Vegetius is the only source afaik who mentions a 'ducentenarius' as a rank between the centurion and the primus pilus. Vegetius was in all probability wrongly equating ‘ducenti’ into ‘ducentenarius’. A classic example of a ‘ducentenarios’ however is not known from the military, but from horse-racing, as a horse with two hundred victories (Diocles). As a result we cannot be sure if Vegetius, as he often did, made something up or mentioned the actual number of men under the command of a ducenarius. The word ‘ducentenarius’ as a commander of two hundred men is not known before Bede (8th c.).

[Sean Manning]

How much evidence do we have (more evidence -> a higher level of credence is possible if the evidence mostly agrees)
What does other evidence say?
Why did our source say this? Were they an eyewitness? Talked to an eyewitness? Read it- where? Hearsay? Didn't believe it at all but was trying for rhetorical effect?

Most of these questions are impossible to be answered for any source in Antiquity.

Isn't that overstating it? In the case of Vegetius, for example, we are pretty sure when and in what context he was composing; we know some of his sources, although they are all lost; and his general method and purpose (he is digging in Latin books to learn the good old way Romans used to fight in the belief that this will solve the military problems he perceives in his own day). We are rarely certain of all of these things, but the same goes for most historical sources.

[John Conyard]

Robert, as a quick aside, just how many sources before Vegetius give a tent party of eight men?

[D B Campbell]

If memory serves Gallienus consolidated the cavalry units of the legions into separate bodies for use as strategic or operational reserves.

See Ancient Warfare magazine II.6 (Dec/Jan 2009), pp. 8-11 ("Coinage and cavalry: The sources for Gallienus and his equites"), for a more critical view. :wink:

Robert, as a quick aside, just how many sources before Vegetius give a tent party of eight men?

One?

[John Conyard]

One, unknown, author comes to mind.

I would be interested in any others............

[Robert Vermaat]

Most of these questions are impossible to be answered for any source in Antiquity.

Isn't that overstating it? In the case of Vegetius, for example, we are pretty sure when and in what context he was composing; we know some of his sources, although they are all lost; and his general method and purpose (he is digging in Latin books to learn the good old way Romans used to fight in the belief that this will solve the military problems he perceives in his own day). We are rarely certain of all of these things, but the same goes for most historical sources.

I was especially thinking of the questions:
Why did our source say this?
Were they an eyewitness?
Talked to an eyewitness?
Read it- where?
Hearsay?
Didn't believe it at all but was trying for rhetorical effect?

As long as an author fails to specifically answer these questions, there's no way of answering them. Only a few authors mention the sources where the found their information, even fewer mention how they obtained it from other sources.
It's also not valid to ask these questions, as they belong to the appraoch of modern history. Ancient history was a very different thing, and should be judged accordingly.

[ValentinianVictrix]

We have to balance Vegetius' description of the composition of the ideal legione with what those at the time acquainted with them say. Is there any evidence at all of a Vegetius type legione made up of its component parts actually being deployed in the Late Roman period?

Well, we do have Ammianus claiming that the legiones were still made up of maniples, centuries and cohorts. We have papyri detailing payments during the 4th Century to cohorts etc. We also have Ammianus stating that the light infantry were stationed behind the lines, screening deployment, harrying the enemy and then moving behind the lines to support them. And we also have in one of Julian's Orations stating that unarmoured archers were stationed behind the Legiones supporting them. So, we have some sources well acquainted with military matters at least backing up part of Vegetius' description of the legione.

[Sean Manning]

Most of these questions are impossible to be answered for any source in Antiquity.

Isn't that overstating it? In the case of Vegetius, for example, we are pretty sure when and in what context he was composing; we know some of his sources, although they are all lost; and his general method and purpose (he is digging in Latin books to learn the good old way Romans used to fight in the belief that this will solve the military problems he perceives in his own day). We are rarely certain of all of these things, but the same goes for most historical sources.

I was especially thinking of the questions:
Why did our source say this?
Were they an eyewitness?
Talked to an eyewitness?
Read it- where?
Hearsay?
Didn't believe it at all but was trying for rhetorical effect?

As long as an author fails to specifically answer these questions, there's no way of answering them. Only a few authors mention the sources where the found their information, even fewer mention how they obtained it from other sources.

It's also not valid to ask these questions, as they belong to the appraoch of modern history. Ancient history was a very different thing, and should be judged accordingly.

Hi Robert,

I also disagree that we cannot answer these questions at all unless the author tells us. For example: if the author lived a long time after the events in question, clearly he was not an eyewitness and did not talk to eyewitnesses. Also, just because an author tells us his methods doesn't mean we should be sure those are the methods he actually used (although we can take it as probably true unless the evidence suggests otherwise). We still have to test it against the works themselves, what else we know about the author and his contemporaries, and so on.

I'm surprised to see you say that "it is not valid to ask these questions", because every skilled ancient historian I know of does. Haven't you written articles on our written sources for Sub-Roman Britain and what each was probably trying to do, or on whether Geoffrey of Monmouth really used lost old books? Greeks and Romans and Jews who wrote histories usually aimed at different things than modern academic historians do, but modern academic historians of any period are still trying to form a best guess at what really happened to something in the past. I think ancient Greco-Roman history differs from other kinds of history in accidents not essence: I think there is a continuum, from "very well documented" (Canada in 1940) to "very poorly documented" (Babylonia in 1000 BCE) which shapes the types of questions we can ask and the methods we use on them. For example, ancient historians have to use weaker (coins) and less reliable (tertiary sources like Diodorus) forms of evidence than historians of better documented periods. Maybe we need a new thread on historical methods?