[split] Distances between files and ranks

[Renatus]

Nathan wrote:
Arrian does not say that there are five centurions in the first cohort. He says nothing about the number of centurions.
 
DeVoto translation page 115, The Expedition Against the Alani: “five centurions who {are} rear chiefs of the first cohort.”

In the edition that DeVoto was using (Roos) πἐντε is bracketed. The apparatus reads, 'supplevi < πἐντε>' which means that the editor has supplied the word and it is not iπ the original. In other words, Arrian did not say that there were five centurions in the first cohort.

[Nathan Ross]

You can find the answer in Tacitus.

Do you have a reference? It's a little obscure otherwise!

In fact we could also look in Josephus (Wars III.6.2): "Vespasian set out from Ptolemais... with his army arranged in the usual Roman marching order" - that's six abreast; so a formation six or twelve or eighteen deep...

You need to reread my previous posting.

I did, but thanks for the clarification!

Rather than having the first maniple drawn up in one long line two deep, with the second maniple behind it, why not have both maniples side by side, with one century behind the other? That way you'd still have each line four men deep, but the posteriores would be behind the priores.

I have 10 feet long calculations... how can you be so sure it cannot be done?

I was being entirely practical. It's possible that Roman cavalry horses were slightly smaller than modern horses, but not that much smaller, and they would not have behaved any more like donkeys. You cannot get cavalry and infantry to march abreast in column without opening very long spaces between the marching men.

Read Polybius’ account of the legion on the march and you will answer your own question.

Polybius says nothing, as far as I know, about width of columns or depth of ranks in formation. He says that the army could march in three columns in open country - was that what you mean?

But I was asking about your proposed formation, based on Sallust, not that of Polybius.

Anything is simple in ones mind’s eye.

Certainly! But are you saying this manoeuvre was simple, or was not simple?

DeVoto translation...i: “five centurions...”

I see Michael has already covered this. We've also discussed it before...

[Steven James]

Nathan wrote:

Do you have a reference? It's a little obscure otherwise!
 
Mate, do you realise at present I am re-examining the levy of 298 BC. All this time travelling back to Tacitus is giving me time travel lagg. Tacitus (The Annals 1 51), (13 37-38), Josephus (The Jewish War 3 32), Hyginus (The Fortification of the Camp 30)
 
Nathan wrote:
Rather than having the first maniple drawn up in one long line two deep, with the second maniple behind it, why not have both maniples side by side, with one century behind the other? That way you'd still have each line four men deep, but the posteriores would be behind the priores.
 
Yes that can be done, and I did it that way for years. However, I have found it to be wrong, and also it turned out to be a rather big red herring, and I would term it the Cannae for all academics, and historians. When you get into that territory, you get stuck.
 
Nathan wrote:
Polybius says nothing, as far as I know, about width of columns or depth of ranks in formation. He says that the army could march in three columns in open country - was that what you mean?
 
Polybius does describe going from column to battle order and the placement of the baggage. It is very informative. Polybius also mentions the Roman army being attacked from any direction and how the army would respond to this. I have not found one modern scholar that has been able to replicate what the Roman army did when attacked from the front or the rear. Most just cover being attacked on the right flank.
 
I spent a lot of time over the years in working out how the mechanics of what the legion did when attacked from any direction. Each time it failed, I went back to the legion’s organisation and started re-examining it over and over again.
 
Nathan wrote:
But I was asking about your proposed formation, based on Sallust, not that of Polybius.
 
Polybius and Sallust are one and the same. The mechanics are the same regardless of the period. Nothing much has changed, except the names of the units.
 
Nathan wrote:
But are you saying this manoeuvre was simple, or was not simple?
 
It was simple, extremely simply. But to do it, the army had to halt, to do the last manoeuvre. Until that point, it would be the same as Polybius (achieving battle order in one movement).
 
Well Nathan, you have said nothing on my legion of 12 deep changing to 8 deep.
 

[Nathan Ross]

Tacitus (The Annals 1 51)

This passage just says that Germanicus split his army into four columns to ravage the enemy country. He then made his return march in what appears to be agmen quadratum formation (although T doesn't refer to it as such) 'prepared both to march and to fight'. There's nothing here about the width of the columns or the depth of the battle formations, which is what we were discussing. What else are you seeing here?

It was simple, extremely simply. But to do it, the army had to halt, to do the last manoeuvre. Until that point, it would be the same as Polybius (achieving battle order in one movement).

Yes, that sounds pretty simple to me too. What's the difficulty?

you have said nothing on my legion of 12 deep changing to 8 deep.

You mean the thing about the pilani not being with the legion, or something? I didn't really understand that part, I'm afraid. Do you mean that Arrian's 8-deep formation is missing four extra men in depth, because those men are 'pilani' and are away guarding the camp? So his formation should be twelve deep?

If so, what do other twelve-deep formations do about guarding the camp? And why would you need a full third of your soldiers to guard the camp anyway?


Meanwhile, going back to Deryk's original post (which was actually about the deployment of Suetonius Paulinus against Boudica in AD61):

some anomalies regarding the distances between the legionaries especially if they were 8 deep... Firstly when the pilums were thrown there would have to have been 3 foot between each man to allow for the throw therefore they couldn't have been in close order at that time.

I was looking again at Arrian's Against the Alans; this is the most detailed account we have of a battlefield formation of a date reasonably close to AD61.

Section II, about the march, is very clear that the entire infantry contingent moves in fours: "The formation should be four soldiers wide... foot soldiers should be drawn up in fours... This legion should also be drawn up in fours."

In Section VII, we have the deployment: "They should deploy in eight ranks and their deployment should be close ordered. And the front four ranks of the formation must be of spearmen, whose spearpoints end in thin iron shanks... Those standing in second, third and fourth rank of the formation must hold their spears ready for thrusting... The following ranks should be of the javelineers. The ninth rank behind them should be the foot archers."

In Section IX, we have the tactics: "the first three ranks should lock their shields and press their shoulders and receive the charge as strongly as possible in the most closely ordered formation bound together in the strongest manner. The fourth rank will throw their javelins overhead and the first rank will stab at them and their horses with their spears without pause."

So a four-abreast march deploys as an eight deep close-order formation, with a single line of archers at the rear. This sounds to me like a 80-man 'Hyginian' century arrangement, with the legion drawn up in two lines of centuries, each century 20 men x 4 men.

The most important thing is that the first three ranks have to be close enough together that they can lock shields to repel cavalry. And note that Arrian only has the fourth rank thowing javelins, over the heads of the men in front; all these men, I would suggest, have been trained to work together in formation. He doesn't tell us what ranks 5-8 are doing!

So we could have the forward century in four close ranks, then a slight gap, then the rear century also in four ranks, to make up Arrian's array.

[Bryan]

When Metellus at the Muthul River became aware that he was walking into a trap, Metellus halted his army, and changed its march order formation. The right flank, which was nearest the Numidian army, Metellus strengthen with three lines of reserves (subsidia). Sallust (The Jugurthine War 49 4-6) Here we find Metellus had to halt his army in order to change his order of march, and it is a vital clue as it is the opposite to Polybius and Tacitus. What Metellus is doing has been written about by other ancient authors and totally ignored by modern scholars.

Based on the context of Sallust's description of the battle it seems that Metellus was marching into a plain inside a sort-of boxed canyon surrounded on two sides by ridges, left and right, the far side by the river Muthul, and with the army exiting other hill/ridge from their direction of travel. Scouts saw Jugurtha's forces on top the ridge on the right, which would have been at around 2 o'clock to their direction of travel at the exit into the plain. Metellus correctly judged that it was an ambush that had been compromises and knew it was a trap to march into the plain in standard march order, so Metellus maneuvered his army to triplex acies battle array, with skirmishes between maniples, to counter the threat on the right flank. Which meant the army after reassembling would march forward toward the river (with Rutilius Rufus commanding the left wing of cavalry and light forces to secure a position near the river to assemble a camp), with the rest of the column able to face right quickly if necessary to form into immediate battle formation of triplex acies to withstand an attack by Jugurtha's forces who were atop a ridgeline parallel to Metellus' direction of travel to the river. 

Other accounts of marching order and deduction by scholars suggests that in terms of infantry it was typical for in the Mid to Late Republic for consular armies for the Extraordinarii to lead the way as the vanguard, then the rest of the Socii Dextra Ala, then the two Roman legions, then the Sinistra Ala. With that formation they could, if necessary deal with flanking threats, but more importantly it was a formation that allowing them to hit a pivot point at the fore, column right, and then form into battle array to deal with a frontal threat. But it wasn't optimal for a guaranteed flanking battle. So at the Muthul River, had they stayed in that marching order it would have been basically backwards. So Metellus' move to shift the marching order to right facing triplex acies made sense. 

However, there is no way of knowing what the actual battle array was in terms of rank and file width and depth, its absolutely not mentioned in the source, so its pure speculation what it was in the march and battle, or if they shifted again, likely, once once the force exited the narrow exit from the hills into much wider open plain.

I'm pretty sure I figured out where the battle happened based on descriptions: Muthul Battle Location. Metellus' army was likely following the Muthul River and was coming south on the road identified now as P-17 from what would later be called Bulla Regia. Jugurtha's forces were likely positioned along the east-west ridge identified as Foret Nord de Nebeur. There was no reservoir or dam in 109 BC , just the river to the west, that was Rutilius Rufus' destination to establish the Roman marching camp. The battle occurred in the plains between Nebeur and the river, with Metellus holding the center, Marius the right. Upon the Roman army entering the plain Jugurtha sent a detachment that closed off the exit into the plain that Metellus' army had marched from, sealing the Roman army inside the sort-of boxed canyon. Then another Numidian force of infantry and cavalry, to include elephants, attacked Rutilius Rufus' wing near the river (which had marched ahead of the main body), with the bulk of Jugurtha's army of infantry and cavalry attacking the Roman center and right.

[Nathan Ross]

Metellus maneuvered his army to triplex acies battle array, with skirmishes between maniples, to counter the threat on the right flank.

That sounds right - and the map looks good too!

The only thing I don't get is why he brought up three lines of reserves to strengthen his flank - he'd only need two extra to form the triplex acies. Unless one of the lines was made up of skirmishers, perhaps on the extreme right? Or is there another explanation?

[Bryan]

Metellus maneuvered his army to triplex acies battle array, with skirmishes between maniples, to counter the threat on the right flank.

That sounds right - and the map looks good too!

The only thing I don't get is why he brought up three lines of reserves to strengthen his flank - he'd only need two extra to form the triplex acies. Unless one of the lines was made up of skirmishers, perhaps on the extreme right? Or is there another explanation?

Its a kind of confusing battle description. It seems like Sallust is describing a formation of triplex acies but maybe not. He starts off by mentioning maniples (specifically in reference to placing skirmishers in between the gaps), but halfway through the battle he starts referring to cohorts for the first time referencing Romans and not Socii, which is why most modern historians when describing the evolution of the manipular legion to cohortal generally start with 109 BC. 

After re-reading the source numerous times to try to get a feel for what happened, I think the main body (as it could only apply to them, not Rutulius Rufus' advanced wing) had three lines of infantry in column, probably in double files in order to close up the width of the marching column, and were flanked on the right with either skirmishers or cavalry, who changed positions once they entered the plain. Either way, I can see Metellus' army stopping and shifting again when it became obvious that Jugurtha had closed off the entrance to the plain, and when Jugurtha's forces descended the ridge and entered the plain themselves. At that point the battle would have been imminent, while at the same time Metellus needed to reach the river for safety. With much more room to maneuver, he could have quickly shifted all the lines into deeper formations to be ready for the eventual Numidian attack.

[Theoderic]

Steven James wrote:

Here’s my answer.
 
      

Thanks for this - excellent.

---

Nathan wrote:

In Section IX, we have the tactics: "the first three ranks should lock their shields and press their shoulders and receive the charge as strongly as possible in the most closely ordered formation bound together in the strongest manner. The fourth rank will throw their javelins overhead and the first rank will stab at them and their horses with their spears without pause."

Firstly thanks for getting Robert to split out this thread, Secondly really impressed with everyone's expertise - no idea where "simple" comes from - seems really complex to me.

If we look at a century being 8 deep in ranks then it should be 10 files wide or 30 feet in "close order" - doubling to 16 rank deep in "open order" but still 10 files wide.

With the description that you state above I don't understand how the first 3 ranks lock their shield together without widening the files - or is that what happens? If that is the case how does the first rank stab with their spears if the first three ranks have combined and are now in the front rank?

Also would the 4th rank be in "open order" when they threw their javelins?
.
I apologise in advance if this seems too simplistic 



  

[Nathan Ross]

I don't understand how the first 3 ranks lock their shield together without widening the files ... Also would the 4th rank be in "open order" when they threw their javelins?

I would assume that the front rank would have to kneel or crouch, and the third rank men are holding their shields above the heads of the two men in front. Something similar is shown on one of the Mainz column bases I think. But all three would be pressed in very tightly together, while still occupying the same frontage.

If there's a gap between the fourth rank and the fifth then the fourth rank men might get a couple of steps 'run up' to throw javelins - although Arrian rather implies they're thrown from a standing start.

Here's a illustration of Arrian's formation, from Ancient Warfare. Interesting the artist has given them oval shields! I'm not sure why this century appears to have 128 men in it though...



I would think the front three men would need to be packed in closer, to get their shoulders into their shields as Arrian suggests, and the men behind them could perhaps be spread out backwards a bit to get some space for throwing javelins (they do seem to be sort of tossing them quite lightly here!). But it shows the sort of depth and numbers we might be looking at quite well.

It also show 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!

[Steven James]

In relation to Arrian, Devoto made the conclusion there was five centurions as:

 
“In the second century a.d. each tribune (chiliarchos) normally had five centurions (hekatontarchoi) under his command. Thus the restored pente most likely is correct.”

[Renatus]

In relation to Arrian, Devoto made the conclusion there was five centurions as:

 
“In the second century a.d. each tribune (chiliarchos) normally had five centurions (hekatontarchoi) under his command. Thus the restored pente most likely is correct.”

Where is this? I can't find it.

[Steven James]

Michael wrote:

Where is this? I can't find it.
 
It is from a private email I had with DeVoto.

[Renatus]

Michael wrote:

Where is this? I can't find it.
 
It is from a private email I had with DeVoto.

Did he say where the bit about each tribune commanding five centurions comes from?

[Steven James]

Michael wrote:

Did he say where the bit about each tribune commanding five centurions comes from?
 
In the Teubner text of Arrian's "Art of Tactics"

[Nathan Ross]

Talking of very deep or dense formations, I just came across this, in Frontinus Stratagems II.3.22:

"In the battle against Caesar at Old Pharsalus, Gnaeus Pompey drew up three lines of battle, each one ten men deep, stationing on the wings and in the centre the legions upon whose prowess he could most safely rely, and filling the spaces between these with raw recruits."

That would make an overall formation of thirty ranks deep!