[split] Distances between files and ranks

[Renatus]

the next part about the tribunes was a different train of thought
 

Can you enlighten me on that then, please?

[Nathan Ross]

Nathan wrote:

...we have to assume that the sources mean what they say, and not that they made mistakes, altered numbers or fudged things, just to suit our own theories.
 
You mean like your example of the Perge document. Really, Nathan, you are contradicting yourself.

Nope, not at all. The discussion of the Perge inscription involved all the numbers on the list, did not leave any out, did not change any and did not assume that any of them were mistakes or needed to be amended or corrected in any way.

You've mentioned this several times before. If you had read through that previous thread fully and in detail, I think you would see that the two approaches are not at all comparable.

Show me proof the figure of 30 ranks has not been rounded from 28 ranks.

How would anyone 'prove' such a thing? The only evidence we have for it is Frontinus saying that there were three lines, ten deep each. If he did not mean exactly what he wrote, why did he write it?

Even if it was 30 ranks and the camp guard were additional, Pompey’s legionaries would increase from 45,000 men to 48,000 men... However, I have worked with Caesar’s figure of 45,000 men and followed Roman military doctrine going back to the early republic...

Frontinus does not tell us how wide the formation was, or how many men it totalled - only that those men were in three lines each ten deep. You have mentioned often enough that the estimates of army numbers differ in ancient sources, so using evidence from one writer to make accurate calculations of the numbers in another writer is not a sure method.

But I do not believe there was a 'Roman military doctrine going back to the early republic' that would determine things like numbers of men sent to guard camps.

[Steven James]

Nathan wrote:

How would anyone 'prove' such a thing? The only evidence we have for it is Frontinus saying that there were three lines, ten deep each. If he did not mean exactly what he wrote, why did he write it?
 
Why does Polybius write that Publius Scipio was sent to Iberian with 20 ships? Why does Livy write that Publius Scipio was sent to Iberian with 30 ships? The answer is due to rounding the numbers.
 
Why do Appian and Caesar give the size of Caesar’s army at 22,000 men? Why do Eutropius and Orosius give Caesar’s army at less than 30,000 infantry? What is happening is Eutropius and Orosius are giving the total of Caesar’ infantry before the deduction of the 1,500 camp guards, the 3,000 men of the fourth line, and the 1,500 antesignani allocated to the cavalry. Appian and Caesar are providing the number of men left after these deductions have been made. In total, Caesar’s army amounted to 28,000 men, which omits the auxiliaries, calculated at 9,000 men:
 

Hastati            7500 men

Princeps          9000 men

Pilani               4500 men

Total             21000 men

Antesignani     1500 men

Fourth line      3000 men

Camp guards   1500 men

Total             27000 men

Cavalry            1000 men

Total             28000 men

 
Appian gives Caesar’s army at 22,000 men, of which 1,000 were cavalry. This works out to be 21,000 infantry and 1,000 cavalry, which matches my calculations above. I have based the number of antesignani on the whole frontage of Caesar’s army. As the antesignani were front line men, the figure of 1,500 works. I have other data from Caesar about the antesignani to collaborate my claim.
 
I found Eutropius and Orosius figure of ‘less than 30,000 infantry, would approximate to 27,000 infantry, which are legionaries.
 
The paper I did on Pharsalus has since been rewritten, with more insights added. Most modern scholars simply take Caesars 22,000 men and divide it by 80 cohorts to arrive at each cohort having 275 men. And then they jump up and down with excitement claiming how under strength Caesar’s army was. However, they forget that Appian states the army numbered 22,000 men of which 1,000 were cavalry, so you should get 21,000 infantry and 1,000 cavalry. Also Caesar mentions 22,000 men, not 22,000 infantry.
 
So Nathan, Caesar has given Pompey’s army at 45,000 men, and has not taken into account those deducted as camp guards, whereas Caesar’s figure of 22,000 men is the number of legionaries and cavalry left on the battlefield. And this makes sense as Caesar would know what he had done with his army. However, by omitting the number of camp guards, the antesignani and the flanking cohorts makes his army smaller and would be good propaganda for himself.
 
So at Pharsalus, Pompey’s 42,000 legionaries arrayed 1,500 men wide by 28 men deep, faced Caesar’s 21,000 legionaries arrayed 1,500 men wide by 14 men deep.
 
To answer your question, Frontinus has used the depth of Pompey’s legionaries before the camp guards were deducted or just rounded the 28 to 30 deep. Whichever method, Frontinus is doing what other ancient authors do all the time.
 
Have a look at all the papers on Pharsalus and see if any have studied the numbers as I have.
 
Nathan wrote:
You have mentioned often enough that the estimates of army numbers differ in ancient sources, so using evidence from one writer to make accurate calculations of the numbers in another writer is not a sure method.
 
You are quite mistaken. And it is important not to take things out of content. For example, all the various numbers given for the Roman army at Cannae can be reconciled and are one and the same. It is what some omit that makes the difference. Plutarch has 88,000 Romans in battle array. His mention of battle array refers to those on the battlefield. Livy has 87,000 Romans at Cannae. The difference between Livy and Plutarch is Plutarch has included all the officers, standard bearers and musicians. Missing from his total are the artificers, which remained in camp. So when I did the maths and got Livy’s 87,000 men and then added the rest I got 88,000 men. Well what can I say; I must be doing something right.
 
Nathan wrote:
But I do not believe there was a 'Roman military doctrine going back to the early republic' that would determine things like numbers of men sent to guard camps.
 
Seriously! The early republic is beyond your expertise. So how can you make such a statement? And opinion is not fact.
 
At the battle of Silva Arsia in 509 BC, Dionysius (5 15) refers to those soldiers guarding the field camp as the triarii, and those troops acting as the reserve also as the triarii. At the battle of Longula in 486 BC, Dionysius (8 86) mentions the triarii, because they were the oldest men, guarded the camp and that they also fought in close order as a reserve force on the battlefield. Dionysius (9 12) has the triarii accompanied by the artificers guarding the camp at the battle of Veii in 480 BC.
 
On occasion, Dionysius (9 61) uses the term “older men” and “veterans of the reserve” as guarding the field camp. This means the oldest of the triarii guarded the camp. Livy (2 47), (4 19) also mentions the triarii as guarding the field camp. Livy (44 38 6) also has the triarii guarding the baggage camp and claims the triarii were not regarded as the worst of the soldiers. Dionysius’ description of the triarii guarding the camp and also acting as a reserve, highlights they could do both tasks simultaneously when desired by a consul.
 
You can dismiss the above references as anachronistic, but before you do, prove it.
 
Nathan, it doesn’t matter what I put forward as evidence. With you and the usual suspects, I will always be wrong. As Theodoric replied to you, even with a time machine that still would not be sufficient evidence for you. You’ll find a way to try and make it wrong. In truth, I have many people personally contacting me about my research and many claim it has opened doors for them. I have found some of my papers have been translated into Russian. The odd public snips I get are from you and the usual suspects on this forum, and some sad wargame designer, who found me research did not match his wargaming view of the Roman legion. Professor Roth contacted me and wanted to read my work, and stated he was willing to help me in any way possible. I sent him the first section on the early republic from 509 BC to 407 BC, and he replied I knew nothing about the Roman legion, but did not address one issue about what I sent him. Since then Roth is now following me on academia. Go figure that out.
 
Unfortunately, the very early republic, especially in relation to the Roman army has invited any real study. It is just a blank canvass. However, I have found that to understand the Roman legion, the early period must be understood, otherwise you will never know how the Romans arrived at the legion of the principate.
 
Here’s what I found, the Roman legion started at 2,400 men, increased to 3,600 men, and then 4,800 men and finally finished at 6,000 men. The period of the 3,600 man legion was increased to 4,800 men by adding 1,200 velites, and then in Caesar’s time, 1,200 auxiliaries (archers and slingers).
 
All legions, regardless of size had a combined depth of 12 men. Therefore, the legion went from 200 men wide, to 300 men wide, to 400 men wide and then 500 men wide. And I have found the rationale behind this, which is covered in the book.
 
Is it true that people in the same fields of research, if someone knows more, the others don’t like that person?

[Nathan Ross]

jump up and down with excitement claiming how under strength Caesar’s army was.

Since Caesar himself mentions that his army was depleted, I don't see any reason for anyone to jump up and down about it.

Caesar has given Pompey’s army at 45,000 men, and has not taken into account those deducted as camp guards... So at Pharsalus, Pompey’s 42,000 legionaries arrayed 1,500 men wide by 28 men deep

Civil War, III. 88: Pompeius's infantry line "made up the number of one hundred and ten cohorts. These forces amounted to forty-five thousand men, and about two thousand reserves who had come to him from the beneficiaries of his former armies; and these he had distributed throughout the whole force. Seven remaining cohorts he had placed on garrison duty in the camp and the neighbouring forts... he had stationed his whole cavalry and all his archers and slingers opposite the enemy on the left wing."

So Pompeius's total legionary infantry in the acies appear to number 'about' 47,000, according to Caesar. This does not include the seven 'remaining' cohorts in the camp. How do you get 42,000?

Have a look at all the papers on Pharsalus and see if any have studied the numbers as I have.

I very much doubt they have. And I find your devotion to combing through the sources and picking out all of these numbers very impressive. I still do not agree with your conclusions though.

Many of your ideas appear to rely on the notion that ancient writers, or military commanders, were using exact figures for troop numbers, drawn from some sort of chart or list, down to numbers of men in particular ranks, horses, artificers, etc, and/or that they were drawing these numbers from a fixed mathematical formula.

I prefer to believe that both commanders and historians relied (as they do to this day) on approximate figures - perhaps based on eyewitnesses just counting up subunits or standards and making on the spot calculations, as we know soldiers were trained to do - with exact figures only when available and guesswork when not, rounding up or down as they saw fit.

These approximate figures can give us a good general idea of what was going on, but are seldom complementary. Reality is a lot messier than theory, and any military commander will use all of the forces available to him at any given time, not those directed by some formula also available (in times of civil war) to his enemy!

And opinion is not fact.

You've said this before, but I don't know why. Very little of what we've been discussing is 'fact', as there's no way for us to verify it independently. All we have is various perhaps more-or-less accurate figures from various ancient writers, who may or may not themselves have been drawing on more-or-less-accurate sources. All we can do is interpret these figures and these sources in various ways to try and get a picture of what might have been going on.

In other words, it's neither opinion nor fact. It's interpretation of historical sources.

You can dismiss the above references as anachronistic, but before you do, prove it.

Nobody is disputing that the triarii were often used to guard camps and act as reserves during the Republican period. What does seem anachronistic is the idea that because they did this in the republican era the practice must have continued throughout Roman history in some way, or that it was enshrined in a 'doctrine' followed religiously by Roman commanders - something for which we have no evidence at all and which no source mentions.

As Theodoric replied to you, even with a time machine that still would not be sufficient evidence for you.

If Theoderic himself has told me something, then I definitely have a time machine!

(aha, not that Theoderic! But I don't think it was Deryk either...)

All legions, regardless of size had a combined depth of 12 men.

I still don't see how that follows. Armies were arrayed with differing depths, depending on terrain, opponents etc. Our sources suggest this, and I see no reason to assume otherwise.

[Steven James]

Nathan wrote:

So Pompeius's total legionary infantry in the acies appear to number 'about' 47,000, according to Caesar.
 
You’re adding the 2,000 reservist to the 45,000 men. How can you be sure they are not part of the 45,000 men and should be subtracted?
 
Nathan wrote:
I still do not agree with your conclusions though.
 
We are in agreement then. We both don’t agree with each other’s conclusions. Some time back on the Zama thread (the battle that never was), I showed how Polybius arrived at the Carthaginian army of 93,000 men. Strange isn’t that no other modern scholar picked up on that.
 
Nathan wrote:
Many of your ideas appear to rely on the notion that ancient writers, or military commanders, were using exact figures for troop numbers, drawn from some sort of chart or list, down to numbers of men in particular ranks, horses, artificers, etc, and/or that they were drawing these numbers from a fixed mathematical formula.
 
Nathan, you have surprised me. You have fully understood what I have been discussing for some years. That chart of list as you describe it is the Servian constitution. Musicians and artificers are also an integral part of the Servian constitution. The voting procedure of the Servian constitution is conducted by the men arrayed in ranks. This has been discussed by Dionysius and Livy. Unfortunately, the Servian constitution and its relationship to the legion has not been studied in any great depth, which is a shame as it provides the greatest insights in the history of the Roman legion.
 
Nathan wrote:
I prefer to believe that both commanders and historians relied (as they do to this day) on approximate figures - perhaps based on eyewitnesses just counting up subunits or standards and making on the spot calculations, as we know soldiers were trained to do - with exact figures only when available and guesswork when not, rounding up or down as they saw fit.
 
If you mean approximate figures equate to paper strength figures for ancient armies, then we are in agreement. As for making up numbers, I have many accounts of the size of the Roman army being used for the size of the enemy.
 
Funny how you question me about why would Frontinus round Pompey’s depth, when here you mention “rounding up or down as they saw fit.” I love your style.
 
Nathan wrote:
What does seem anachronistic is the idea that because they did this in the republican era the practice must have continued throughout Roman history in some way, or that it was enshrined in a 'doctrine' followed religiously by Roman commanders - something for which we have no evidence at all and which no source mentions.
 
Sorry, there is no 12 step program provided by the ancient sources. To find the evidence, try and understand the various legion numbers found throughout the primary sources, and why they are at variance. I work in chronological order, so when I cover the principate, I only use sources of that period. Tacitus is a gold mine of information.
 
Nathan wrote:
I still don't see how that follows. Armies were arrayed with differing depths, depending on terrain, opponents etc. Our sources suggest this, and I see no reason to assume otherwise.
 
Standard deployment. There are variations due to tactics and terrain. Such deviations from the standard are well and truly covered in the book, which at the moment could be separated into two or three volumes. At present I am polishing volume one.

[Nathan Ross]

You’re adding the 2,000 reservist to the 45,000 men. How can you be sure they are not part of the 45,000 men and should be subtracted?

The text of Civil Wars III.88 seems very clear to me (paying attention to the words and phrases underlined in my quote):

These forces (i.e. the 110 cohorts that made up Pompey's infantry line) amounted to forty-five thousand men, and about two thousand reserves who had come to him from the beneficiaries of his former armies; and these he had distributed throughout the whole force. Seven remaining cohorts he had placed on garrison duty in the camp and the neighbouring forts.

You'd need to check the original Latin very carefully to make sure, but that 'and' certainly appears to mean that the 2000 reserves were additional to the 45,000. The following clause states that the 2000 were mixed with the other troops, giving 47,000 total.

The seven cohorts in the camp and forts were 'remaining', so they are not counted as part of the figure either.

you question me about why would Frontinus round Pompey’s depth, when here you mention “rounding up or down as they saw fit.”

There is a difference, I think, between taking a figure like (say) 24,568 - which might be the very accurate tally of an army's total number on the morning of battle, complied from unit strength reports - and rounding it up to 25,000, or down to 24,000, or saying 'more than twenty thousand' or 'fewer than thirty thousand', and taking a very simple and specific reference to a formation ten men deep and assuming it must really mean eight men deep, because your own calculations tell you that this must be so, and you can't make the numbers work otherwise!

[Renatus]

You’re adding the 2,000 reservist to the 45,000 men. How can you be sure they are not part of the 45,000 men and should be subtracted?

The text of Civil Wars III.88 seems very clear to me (paying attention to the words and phrases underlined in my quote):

These forces (i.e. the 110 cohorts that made up Pompey's infantry line) amounted to forty-five thousand men, and about two thousand reserves who had come to him from the beneficiaries of his former armies; and these he had distributed throughout the whole force. Seven remaining cohorts he had placed on garrison duty in the camp and the neighbouring forts.

You'd need to check the original Latin very carefully to make sure, but that 'and' certainly appears to mean that the 2000 reserves were additional to the 45,000. The following clause states that the 2000 were mixed with the other troops, giving 47,000 total.

The seven cohorts in the camp and forts were 'remaining', so they are not counted as part of the figure either.

There is no 'and' in the Latin. That is added by the Loeb translator; the Penguin translator adds 'plus'. Without attempting a retranslation but adapting the Loeb, the passage could read: 'These amounted to 45,000, about two of veterans who had come to him from the beneficiaries of his former armies; these he had distributed throughout his whole force.' Obviously the word 'thousand' must be understood in relation to the veterans but without the 'and' this could indicate that these men are to be taken as part of the 45,000. The seven cohorts guarding the camp and forts do appear to be separate, however.

[Nathan Ross]

There is no 'and' in the Latin. That is added by the Loeb translator; the Penguin translator adds 'plus'.

Aha! Thanks for checking - it just goes to show (again) how important it is to study the original text...

I can see why the translators added 'and' / 'plus' though, as the meaning appears far from clear without those words! It could be read as either:

'These amounted to 45,000, about two [thousand] of [whom were] veterans... these he had distributed throughout his whole force.'

or

'These (the infantry) amounted to 45,000, [with] about two [thousand] veterans... these (the veterans) he had distributed throughout his whole force.'


Is the repeat of 'these' in the original? It seems to be contrasting two separate bodies of men.

[Renatus]

I can see why the translators added 'and' / 'plus' though, as the meaning appears far from clear without those words! It could be read as either:

'These amounted to 45,000, about two [thousand] of [whom were] veterans... these he had distributed throughout his whole force.'

or

'These (the infantry) amounted to 45,000, [with] about two [thousand] veterans... these (the veterans) he had distributed throughout his whole force.'

Frankly, I prefer the first alternative but see below.

Is the repeat of 'these' in the original? It seems to be contrasting two separate bodies of men.

No, the first is haec, the second is quae. The second is better rendered as 'who' or 'which'. Quae also appears in the relation to the veterans 'who came to him . . .' 

[Nathan Ross]

No, the first is haec, the second is quae.

Thanks again!

Is there any possibility in this passage that the two thousand veterans should be subtracted from the total number of 45,000, rather than being included in it or (perhaps) additional to it?

[Renatus]

Is there any possibility in this passage that the two thousand veterans should be subtracted from the total number of 45,000, rather than being included in it or (perhaps) additional to it?

I don't think so. They were 'distributed throughout his whole force'. The word translated as 'force' is acie, which I understand to mean 'battle-line'. This is the term used in the Penguin translation. As Caesar has just described how Pompey had drawn up his forces for battle and said that they totalled 45,000, there seems little doubt that the veterans are included in that number.

[Theoderic]

Nathan wrote:
 
It also shows how important it would be for the men in the front four ranks (at least) to be trained to work together in formation, and for each man to know his place in the ranks and files instantly: any confusion and somebody's getting bashed over the head with a shield, or stabbed in the back of the neck with a pilum!
 
Many thanks for the explanation of the "shield wall".
 
Steven also showed the difference between “closed” and “open” order and the transition from one to the other.

Although obviously the century is the base unit of 80 men so I am assuming that the operational unit in battle formation would have been the cohort (480 men). If these were lined up 12 deep that would have been 40 metres wide in close order – so that would have made the Legion in battle array of 9 cohorts of 480 men plus one cohort of double strength 960 men so that would have given a width of 360 metres plus 80 metres for the 1st Cohort   of some 440 metres.

I am assuming that there was a gap between cohorts to allow for manoeuvres (but perhaps that could be confirmed by someone) so a width of 500 metres for the Legionaries of the Legion would seem to be logical.

If the above is the case for the Legion in AD60 era my next question is how would the cohorts of men transition into the “wedge formation” from “closed” formation on the battlefield.

My last question is;  If a Legion were to charge in the wedge formation after the pilums had been thrown, how did they manage this, at speed, and avoid the dead and dying in their way after the effectiveness of the volley of spears or was the charge a more deliberate advance?

I am looking at this from the perspective of the Boudica battle with Paulinus…..

[Nathan Ross]

If these were lined up 12 deep that would have been 40 metres wide in close order... so a width of 500 metres for the Legionaries of the Legion would seem to be logical.

Or 60 metres wide if they were 8 deep. Arrian seems to think this was dense enough to repel cavalry. Vegetius has his cohorts in two lines rather than the triplex acies familiar from the republic. An 8-deep close-order formation (perhaps two lines four deep?) would give the legion c.600-625 metres width.

The double first cohort was probably a Flavian innovation, but there may have been a (cohort-sized?) veteran vexillatio attached to the Julio-Claudian legion; however, I suggest these might have been used as reserves behind the centre, rather than joining the front lines.

As for Suetonius Paulinus, I would think he would deploy his men (within reason) to fit the width of the defile, rather than choosing only a defile that would fit a certain standard width of formation.

how would the cohorts of men transition into the “wedge formation” from “closed” formation on the battlefield... how did they manage this, at speed... or was the charge a more deliberate advance?

Some descriptions of the cuneus imply an advance in a column - which would either mean changing formation (unlikely) or a strengthened centre that could push outwards into the midst of the enemy. This might have been the purpose of the veteran vexillationes - if they were posted at the rear they could have provided the mass to support a charge by column from the centre of the line.

I would say more a 'deliberate advance' though. They would have wanted to keep formation, and would have been fighting as they went and clambering over any obstacles in the way too, so at jog at best, I would think, speed-wise!

[Renatus]

As for Suetonius Paulinus, I would think he would deploy his men (within reason) to fit the width of the defile, rather than choosing only a defile that would fit a certain standard width of formation.

This is eminently sensible. The sorts of formation we have been discussing may well have applied in the open field. Within the confines of a defile, while the frontage might follow the same principles, the depth would depend entirely upon the number of soldiers and the width of the defile.

[Bryan]

The ridge at Ilerda is identified today (at least it was some years ago). Dodge mentions that the historian Rüstow measured that ridge, finding it equivalent to 360 feet in width at the point that Caesar had three cohorts attacking up it (Caes DBC 1.45-46).

Play with the variables of the size of Caesar's cohorts, and do the math. It will describe the possibilities, depending on the size of the cohorts, of the width and depth of each cohort, at least in Caesar's time.