Roman Battle Formations Mid Republic to Late Rep.

[Macedon]

Macedon,

Can you please describe in detail how you believe the Romans fought. Pick a time period where the maniple styled legions existed, or early cohorts were used and describe how they were composed, organized, deployed and battled in melee.

Great post BTW. For the life of me can't figure out how some of those sources were included. Must have been tired. Also, I don't comprehend Latin or Greek but am curious as to how not one book I have read included your translation meaning of the word phalanx. How is it that every historian I've read got it wrong? If it is true then all the speculation is over, the Romans fought in one superlong continuous phalanx, just in three lines. But then why is there still debate? Why do major historians throughout the last couple hundred years (who also read Latin and Greek) argue with each other about Gaps and such?

I will Bryan. The thing with many scholars is that they do not know ancient Greek, so more often than not they do not check the original texts. Yet, I have not translated the word "phalanx". It is in the original text. The thing is that the translator chose not to translate it as "phalanx" but as a more Anglosaxon "line". If we agree, this is a debate on its own, that in the ancient works a phalanx was indeed always a continuous line, then it is true that the words of Polybius are hard to interpret otherwise. I am not 100% sure that it is so though. I give it a very high probability, especially when comparing the term with how it was used in the Byzantine manuals, where a phalanx is always and definitely ONE of the units in the formation, so when we can have multiple phalanxes in a single line, but I really cannot say I am adamant in my objections. And no I am not trying to be overly modest or something. I have changed the way I view certain aspects of tactics one to many times to be able to declare I am absolutely certain in my interpretations. For me, the part about the Romans not fighting "phalangidon" (=like a phalanx, in the manner of a phalnax) but in maniples (kata speiras = by speirai/maniples) or singly is a stronger argument than any mention of the word "phalanx" because it tactically juxtaposes the two forms of fighting.

Regarding Frontinus and Vegetius, my quotes are from translations and so I do not vouch for their veracity, no matter how recognized a translation might be. I really hoped you might know Latin or that someone who knows Latin can compare the quotes with the originals. You would be amazed at how many things can be perceived otherwise if the originals are studied from a tactical instead of a literary perspective.

And of course, I urge you to double check my translation, I have made mistakes in the past.

[Macedon]

To me, the typical checkerboard formation of the Polybian Romans would be the initial arrangement of the units. They would thus march towards the enemy, facilitating movement and retreat of light infantry and cavalry. I see the posterior centuries deployed behind the ones in front, same order and density. The skirmishers would do their job, attack the enemy line or the enemy skirmishers. When the commander in chief decided it was time to attack or when the enemy started its own charge, the skirmishers would be recalled through the gaps. Up to now, there is no real difference of our systems.

I suggest that in a normal pitched battle, the posterior centuries would swiftly take their position at the left of their "right" centuries, effectively closing the gaps, possibly leaving very small intervals, like a few yards, only in the case of cohorts. In the case of maniples, I do not think that there would be so many intervals left, maybe some for specific reasons, like to facilitate some movement of light infantry to and from the front.

On the other hand, I see no problem of the checkerboard formation being retained during charge if fighting on very rough terrain. It is true, that in that case, gaps would assist the maniples in keeping their order while swarms of skirmishers would exploit the rough ground the maniples would have avoided. This is what seems to be the case in Selassia, what Antigonus did to attack the hill where Cleomenes' brother was in command.

So, in one continuous line, the maniples would engage the enemy in a normal pitched battle. They would try to keep their cohesion with the maniples on the sides and would not individually rush forward or retreat more than a few yards. Of course one would wonder where the novelty in all that is. In my opinion it lies in the training to tactically retreat, which was a good way to draw an enemy to uneven ground, since most armies would just strive to keep their ground (the stratagem of Philip in Cheronea pops to mind), a tactic to be used whenever convenient as well as to their uncanny ability to somehow relieve the front.

Much debate has been made regarding this mysterious relief system. Was it done in units? In whole lines? Would the rear units march forward or the front units march to the rear?

To me, again, every single method would have been an option. We have examples of front lines retreating behind rear lines in the Byzantine manuals, so it was clearly possible to do so. We also have countless examples of units rushing to the help of the front as well as whole lines doing so... So, I choose to not dismiss any of these methods but to accept every single one and have the commander in chief utilize what he deems fit.

I would suggest that the standard method would be the unit by unit relief, not because the sources suggesting so are more than those suggesting otherwise but because, in my personal opinion, it makes sense. If maniple 3 is doing well and maniple 6 is mangled, I would like to be able to allow the former to do its job while supporting/relieving the latter. I propose that someone in the maniple would have been charged with relaying their status to their support units. Each maniple of Principes would initially be responsible to watch the standard of a certain maniple in the front. The maniples were many, so it would be impossible for the commander himself to keep track of their individual needs. If a maniple needed support, there would be a distress sign, possibly stating the kind of support it would need. So, maniple 6 calls for relief and the Principes maniple covering it would get the signal and rush to its support. Once there, I suggest that the following system of actual exchange of lines would take place :

1. The first rank of the Principes maniple arrays behind the last rank of the Hastati maniple. Each rank of Hastati marches to the rear of the Principes, while the latter step forward towards the first rank.

2. Rank by rank (and not by file), this is actually a very safe and quick maneuver up to the first rank, the Hastati would reform behind the Principes maniple. There is absolutely no need for the Hastati to make any special maneuvers, no closing of files, nothing. A simple exchange of ranks.

3. The first rank of the Hastati would of course retreat last. To do so with more safety, each first ranker of the Principes would sidestep presenting his shield forward so that the Hastatus could use his shield as partial cover. If we accept that the Romans fought in open order, this maneuver would be even easier, the first ranker would only have to step back two yards.

4. Once behind the Principes (now this part of the line effectively being doubled in depth), the Hastati would quickly reform, count and then march to an appropriate distance. If it was battle worthy, it would possibly rejoin combat if the Principes needed relief.

Such a method of relief would not be only used by the Romans. I assume that at least the Greeks used it too, but thought it unwise to keep more reserves than the ones that would most possibly be necessary. Furthermore, Greek armies tended to be smaller and their organization was mostly tribal, so it was more difficult to ordain sizable reserves. Another difference is that a spear/pike bearing phalanx will less likely get disordered, while a line of swordsmen would be more prone to it and thus demanded more reserve units to get the upper hand from other sword armed lines or keep fighting against spears and pikes.

[jkaler48]

Here is probably the last time anyone had a try at recreating cohort/legion level tactical formations: http://www.youtube.com/watch?v=0bwh39zqKrI
Final battle scene from the 1960 movie Spartacus. Eight thousand trained soldiers from the Spanish infantry were used to double as the Roman army. A further 2500 extras played Sparticus's army.

[Bryan]

Maybe if we all pooled our money together we could do the same. Say one months beer money goes into a common pool that pays for actors and basic equipment.
Say five hundred people do it, at $100 bucks per person we can go $50,000, probably enough to hire a military unit or a group of sporting teams to come out to a big ass field and beat on each other for a few hours while we try out tactics.

[Bryan]

Macedon,

I referenced a quote earlier a few times from Caesar's commentaries about how the 8th and 9th Legion had formed up close together at Pharsalus, close enough to support each other. What is your take on that? Do you think there were gaps/intervals separating legions during the cohort legions? What about the Primus Pilus Centurion of the 1st Cohort of each legion? How would have he fought off multiple men at once? How did four cohorts from each legion get relieved by three in the second line when the third line of cohorts wasn't committed until the route of Pompeius Magnus' army?

Why put gaps in the army when deploying when it wouldn't matter if they lose order because you can always redress the lines once they stop to prepare for the charge?

[jkaler48]

Maybe if we all pooled our money together we could do the same. Say one months beer money goes into a common pool that pays for actors and basic equipment.
Say five hundred people do it, at $100 bucks per person we can go $50,000, probably enough to hire a military unit or a group of sporting teams to come out to a big ass field and beat on each other for a few hours while we try out tactics.

See this thread: http://www.romanarmytalk.com/rat.html?fu...&id=297678
About testing recreated tactics.

[Macedon]

Good questions,

Macedon,

I referenced a quote earlier a few times from Caesar's commentaries about how the 8th and 9th Legion had formed up close together at Pharsalus, close enough to support each other. What is your take on that?

"[3.89]Caesar, observing his former custom, had placed the tenth legion on the right, the ninth on the left, although it was very much weakened by the battles at Dyrrachium. He placed the eighth legion so close to the ninth, as to almost make one of the two, and ordered them to support one another. He drew up on the field eighty cohorts, making a total of twenty-two thousand men. He left two cohorts to guard the camp. He gave the command of the left wing to Antonius, of the right to P. Sulla, and of the center to Cn. Domitius: he himself took his post opposite Pompey. At the same time, fearing, from the disposition of the enemy which we have previously mentioned, lest his right wing might be surrounded by their numerous cavalry, he rapidly drafted a single cohort from each of the legions composing the third line, formed of them a fourth line, and opposed them to Pompey's cavalry, and, acquainting them with his wishes, admonished them that the success of that day depended on their courage. At the same time he ordered the third line, and the entire army not to charge without his command: that he would give the signal whenever he wished them to do so." DBC, 3.3.89

Unfortunately, the battle of Pharsalus, although documented and described by a number of authors in all or partly (Ceasar, Plutarch in bot the life of Caesar and that of Pompey, Appian, Frontinus...) to me still contains many shady parts. Caesar's mention of the 8th is taken as being posted to the right of the 9th, but where does anyone say that the 9th was posted in the first line? I do not know Latin, so I cannot speak with certainty about these texts, here I only know what the translations say. In my opinion, there are two possible scenarios regarding the placement of the 8th. The predominant one (the one readily accepted by most if not all) would be that it was posted on the right of the 9th at a very small distance, as the text says (almost to make one of the two).

So, if the 8th was placed to the left of the 9th there would normally be a narrow interval between them. The very fact that we are told of such a gap between two legions infers that there would be even smaller ones between cohorts, if any. I would view it absurd to have a 12 yard interval between legions and a 60 yard interval between cohorts, but then.. who can be really certain? So, if we take the scenario that wants the 9th on the right of the 8th, then the narrow gap would indeed enable the two legions to guard each other's common flank and give support to the outermost files, it is thus that I understand "support" here.

Another (I would admit totally unsupported by modern historiography) theory could have the 8th be posted behind the 9th. This is something that comes to mind since there is absence in the translation of any certain hint as to the relative position of the two here or in any part of the description of the battle. Then, Caesar's orders would be interpreted in another sense, the 8th would indeed as a whole support the 9th, effectively forming a second line very close to the front. Maybe the whole of the 9th would be deployed in single line? Now, such an idea is not supported by bibliography and may easily be dismissed by the Latin text itself if there is something there not clearly translated... As a tactical decision it would certainly though not be a first (told you we RomanArmy forumites are prone to wild theories!).

What most puzzled me was the translated text that reads "drafted a single cohort from each of the legions composing the third line". As stands it seems to imply that there were entire legions forming the third line, but that creates problems... Later Caesar informs us that the fourth line was comprised of six cohorts, which would mean that there were six legions in the third line... Too many by any standards! The original reads :

"Ipse contra Pompeium constitit. Simul his rebus animadversis, quas demonstravimus, timens, ne a multitudine equitum dextrum cornu circumveniretur, celeriter ex tertia acie singulas cohortes detraxit atque ex his quartam instituit equitatuique opposuit et, quid fieri vellet, ostendit monuitque eius diei victoriam in earum cohortium virtute constare."

I do not see the word "legio" here, so maybe again, the translation is misleading... Damn I wish I knew Latin! It might mean that one cohort was taken out from each legion but not the ones constituting the third line but from their third line... We know that Casear had 7 legions when he first landed in Greece, we have the numbers of 6 from this book (8,9,10,11,12 and 27), can it be that there were 6 legions on the field? Of course that would create other problems with the remaining cohorts (80 in total), which again implies 8 legions present or 20 rogue cohorts...

Anyways, I am digressing again. The thing is I am trying to see whether it would be possible to place the 8th behind the 9th instead of to its right, as every model of the battle suggests.

Do you think there were gaps/intervals separating legions during the cohort legions? What about the Primus Pilus Centurion of the 1st Cohort of each legion? How would have he fought off multiple men at once? How did four cohorts from each legion get relieved by three in the second line when the third line of cohorts wasn't committed until the route of Pompeius Magnus' army?

I do not think that there would have been a specific battle-plan in action that generals had to follow regarding the placement of legions. I think that they would have deployed them as they saw fit. That could be far apart, one legion here another on a hill nearby, in single line with small gaps, larger gaps, no gaps, one behind the other. I even see cohorts being drawn from legions to be assigned specific duties (such as forming the fourth line in Caesar’s formation at Pharsalus).

So, guessing that your question has to do with legions forming in line, I would see their usual deployment as with narrow gaps between each other, maybe 10-12 yards and even narrower or no gaps between the cohorts posted in front. Cohorts in subsequent lines would have smaller or larger gaps according to their anticipated use and relative strength. The very fact that the cohorts of the rear lines of the legion would most probably be less than those in the front, only seems to verify that support was given when and where necessary, the third line (when present/formed) being a last reserve and rear guard. I do not see whole lines exchange places here except from with the later described Byzantine system that had the front line retreating through the intervals (these could be sizable indeed) of the rear line only to speedily reform and attack filling in these intervals with their men.

The men on the corners of such formations would be in trouble. Of course they would be well armed and probably the best men in the unit but nevertheless, they would be in trouble… I see them getting support from the man on their rear and from light infantry posted in or right behind the interval, but yes, I do see them fight a a disadvantage. This is one reason why I am reluctant to accept any model of an orderly army that has many intervals. I do accept that some would have been retained but not many. Such gaps would also explain the disproportionate casualties sustained by centurions, since it would be them posted at the corners of cohorts and of course legions.

Why put gaps in the army when deploying when it wouldn't matter if they lose order because you can always redress the lines once they stop to prepare for the charge?

I guess you are talking about the marching order. Because you never know where and when the enemy will attack. If the enemy does not move, you would be able to redress. If the enemy did not leave you the initiative though, reforming the line would actually take much more time if not moving in marching but battle formation. Furthermore, the advancement itself is slower when in battle formation, which may make your troops more vulnerable to enemy skirmishes, give you less time to occupy the ground you want to occupy etc. The whole point of a marching formation would be to facilitate cohesion of units and relative order during march. An uninterrupted line marching through rough ground would have men getting detached from their units while circumventing sizable obstacles, that of course does not mean that it was not preferred when an enemy attack was anticipated. Marching in detached units (again, Greeks also employed such tactics) allowed the men to stay with their units and the unit itself marching around such obstacles without losing cohesion even when losing its order. But this has to do with the manipular system. In the case of the later cohortal legions, I see them preferring the relative safety of wide lines to the superior marching maneuverability of the maniples.

A common marching formation was the column. Part of the phalanx itself marching at a narrow width to take its position on the battlefield. Relatively safe when far from the enemy, it was the downfall of Philip at Cynoscephalae, where the right wing of the Romans attacked the Macedonians while they were still taking their places on the battleground reforming from a marching column - that is, still moving in column.
In all, marching and fighting formations address different, often interdependent, issues. This is why they were separate formations a competent general should master. A third type of formation would be the marching order employed in long marches.

Another interesting text is that of Livy in his 29th Book, remember this is about Scipio in Africa, so we are still in the era of the pure manipular era.

“[29.2].The Roman commanders, L. Lentulus and L. Manlius Acidinus, were determined not to let the war spread through any remissness on their part. They united their forces and marched with their combined strength through the Ausetanian territory, inflicting no injury on either the hostile or the peaceable districts, until they came to where the enemy was encamped. They fixed their own camp at a distance of three miles from that of the enemy, and sent envoys to persuade him to lay down his arms. When, however, the Spanish horse attacked a party of foragers, cavalry supports were at once hurried up from the Roman outposts, and a skirmish took place without any special advantage to either side. On the morrow the whole of the Spanish army marched under arms and in battle formation to within a mile of the Roman camp. The Ausetani formed the centre, the Ilergetes were on the right and the left was made up of various nameless tribes. Between the wings and the centre open spaces were left, wide enough to allow of the cavalry charging through when the right moment arrived. The Roman line was formed in the usual way, except that they so far copied the enemy as to leave spaces between the legions for their cavalry also to pass through. Lentulus, however, saw that this disposition would be of advantage to that side only who were the first to send their cavalry through the wide gaps in the opposing line. Accordingly he gave the military tribune, Servius Cornelius, orders to send his cavalry at full speed through the openings. He himself, finding that his infantry were making no progress, and that the twelfth legion, who were on the left, opposed to the Ilergetes, were beginning to give ground, brought up the thirteenth legion who were in reserve to their support. As soon as the battle was restored in this quarter he rode up to L. Manlius, who was at the front encouraging his men and bringing up assistance wherever it was required, and pointed out to him that all was safe on his left and that S. Cornelius, acting under his orders, would soon envelop the enemy with a whirlwind of cavalry. He had hardly said this when the Roman cavalry charging into the middle of the enemy threw his infantry into confusion, and at the same time barred the passage for the Spanish horse. These, finding themselves unable to act as cavalry, dismounted and fought on foot. When the Roman commanders saw the enemy's ranks in disorder, confusion and panic spreading and the standards swaying to and fro, they appealed to their men to break up the enemy while thus shaken and not let them re-form their line. The barbarians would not have withstood the furious attack which followed had not Indibilis and his dismounted cavalry placed themselves in front to screen the infantry. There was very violent fighting for some time, neither side giving way. The king though half dead kept his ground till he was pinned to the earth by a javelin, and then those who were fighting round him were at last overwhelmed beneath showers of missiles. A general flight began and the carnage was all the greater because the troopers had no time to recover their horses, and the Romans never relaxed the pursuit until they had stripped the enemy of his camp. 13,000 Spaniards were killed on that day and about 1800 prisoners taken. Of the Romans and allies a little more than 200 fell, mainly on the left wing. The Spaniards who had been routed on the field or driven out of their camp, dispersed amongst the fields, and finally returned to their respective communities.”
As usual, in my opinion, Livy seems to be describing a battle in terms of how warfare was done in his time. It is as if we are reading about a battle marshaled by Caesar! In any case, we can get precious (even if anachronistic) information.

1.”Between the wings and the centre open spaces were left, wide enough to allow of the cavalry charging through when the right moment arrived. The Roman line was formed in the usual way, except that they so far copied the enemy as to leave spaces between the legions for their cavalry also to pass through. Lentulus, however, saw that this disposition would be of advantage to that side only who were the first to send their cavalry through the wide gaps in the opposing line. Accordingly he gave the military tribune, Servius Cornelius, orders to send his cavalry at full speed through the openings.”

“when the Roman cavalry charging into the middle of the enemy threw his infantry into confusion, and at the same time barred the passage for the Spanish horse.”

The enemy formed sizable gaps for cavalry to pass through. The Romans did so too “between the legions”, copying the enemy. This implies that normally no sizable gaps would have been left. Then he criticizes the employment of such gaps and shows how the Romans took advantage of them, effectively winning the battle! So, we have the employment of sizable gaps by the enemy and the Romans criticizing them and devising a countermeasure to successfully bring them to their own advantage!

2. "brought up the thirteenth legion who were in reserve to their support."

"and bringing up assistance wherever it was required"

So, in the first instance we have a whole legion rushing to the support of another legion (sounds too cohortal, doesn’t it? A whole legion in reserve at the time of Scipio? Where is the triplex acies?) In the second we have the “wherever and whenever necessary” support I deem default.

[Sean Manning]

Great post BTW. For the life of me can't figure out how some of those sources were included. Must have been tired. Also, I don't comprehend Latin or Greek but am curious as to how not one book I have read included your translation meaning of the word phalanx. How is it that every historian I've read got it wrong? If it is true then all the speculation is over, the Romans fought in one superlong continuous phalanx, just in three lines. But then why is there still debate? Why do major historians throughout the last couple hundred years (who also read Latin and Greek) argue with each other about Gaps and such?

The short answer is that Livy and Polybius strongly imply that the Roman army entered combat with gaps as wide as a maniple in its front rank. While this is strange and almost unparalleled, and many historians have tried to rationalize them, its unscientific to ignore the sources which are closest to the thing they describe.

We know that the way the Romans fought changed over time: in Polybius' day the usual fighting order allowed four cubits per file (Polybius 18.29, 18.30.5-9), in imperial times formations seem to have become denser.

[Bryan]

So, if the 8th was placed to the left of the 9th there would normally be a narrow interval between them. The very fact that we are told of such a gap between two legions infers that there would be even smaller ones between cohorts, if any.

Come on, you are making some major assumptions here. Where did you come up with the idea that there would have been a narrow interval or smaller ones between cohorts?
The line from De Bello Civili straight out implies that there were gaps between the legions, that in the case of Pharsalus the 8th and 9th would be stationed so close together as to almost make one super large legion, but not quite, meaning there was still a gap between them. Then Caesar wrote that the legions are supposed to support each other, which generally implies that usually they didn't, meaning that each legion controlled its own battle space and fought its own fight.

As stands it seems to imply that there were entire legions forming the third line, but that creates problems... Later Caesar informs us that the fourth line was comprised of six cohorts, which would mean that there were six legions in the third line... Too many by any standards! The original reads

Caesar makes it clear a few times how legions formed up for battle. here is one example where he tells you straight out how he formed his five legions of infantry into the traditional triplix acies.
"Caesar had three lines, four cohorts out of each of the five legions formed the first line. Three more from each legion followed them, as reserves: and three others were behind these." De Bello Civili, 1: 83

Its the old 4/3/3 formation of cohorts in battle formation.

Caesar later implies that gaps existed between the legions. He writes repeatedly about battlefields where units are pushed back while others hold. Whole legions run but the Roman line isn't lost. How does this happen when they fight in a continuous battle line? It doesn't. Gaps would have been necessary in battle as well as deploying for battle. Units would separate from each other. Unit integrity is a major psychological factor in battle and it doesn't work if everyone is joined at the hip to the units next to them.

I am officially through with the gap debate. This is entirely too tiring to have to debate the same things over and over again. You win! They fought in a nonstop line.

[Crispvs]

All very interesting. Without wishing to distract attention from the main subject of discussion, two things occur to me which might be worthy of mention.

Firstly, although I had never really noticed it before, in the context of this discussion I could not help noticing that Caesar's 80 cohorts would make a nominal ten legion strength but that the average cohort strength was only 250 men, suggesting that each of these cohorts might only contain the equivalent of two maniples, rather than three.

Secondly, I think that , to some extent, it has been assumed that standardised tactics and formations were always employed, but I do not think that this would necessarily be the case, as such regular behaviour would quickly be learned by observant enemy commanders, who would seek to take advantage of it by varying their own tactics to exploit weaknesses that they had identified in the Roman tactics.

This leads me to recall that prior to any battle from the mediaeval period (and probably before) until well into the nineteenth century, there was a council of war, where the commander discussed his proposed tactics with his senior officers and decided on the plan of action for the forthcoming battle. I would have thought that any ancient commander would have had a similar meeting with his senior officers prior to committing his troops in battle, meaning that a variety of tactics could be employed and that all generals and tribunes would be aware of overall plan. The soldiers would all have received training not just in the proficient use of the their weapons and shields but also the various drills which would have enabled them to move in a co-ordinated way on the battlefield.
With soldiers thus trained, their officers, aware of the general's plan could have moved them as the general had wished. There is no need for them to have always done things in exactly the same way. The skill of a general, after all, was not just shown in his management of a campaign as a whole but in his ability to out-think his opposing commander on the field of battle.

Therefore I agree that it is worth analysing the surviving sources for hints of tactics used, but I think it would be naive to think that they formed up in exactly the same way every time. Therefore I think that it is better to concentrate on exactly how they might have managed to employ those tactics. Thus if one legion supported another, exactly what form might that support have taken? If they could withdraw units from the front line, how this this work?
I know that some of these issues are indeed under discussion in this thread, but I worry slightly that a quest has been developing to determine the standard Roman deployment, when in reality there may have been a *typical* Roman style of deployment but there was probably no *standard* deployment. How a commander deployed his troops would vary according to the capabilities of his units, the lie of the land and his knowledge and expectations of the enemy army.

Crispvs

[Macedon]

Come on, you are making some major assumptions here. Where did you come up with the idea that there would have been a narrow interval or smaller ones between cohorts?
The line from De Bello Civili straight out implies that there were gaps between the legions, that in the case of Pharsalus the 8th and 9th would be stationed so close together as to almost make one super large legion, but not quite, meaning there was still a gap between them. Then Caesar wrote that the legions are supposed to support each other, which generally implies that usually they didn't, meaning that each legion controlled its own battle space and fought its own fight.

Of course I am making assumptions, didn't you ask what my personal opinion was? I wrote that as I understand the text, there would have been "narrower intervals or none at all" between the cohorts THAN the narrow interval Caesar left between the 8th and the 9th. Giving measurements was of course purely hypothetical on my part, only using my understanding of things and what data we have on the actual use of gaps from later periods.

I wrote : "I do not think that there would have been a specific battle-plan in action that generals had to follow regarding the placement of legions. I think that they would have deployed them as they saw fit. That could be far apart, one legion here another on a hill nearby, in single line with small gaps, larger gaps, no gaps, one behind the other. I even see cohorts being drawn from legions to be assigned specific duties (such as forming the fourth line in Caesar’s formation at Pharsalus).

So, guessing that your question has to do with legions forming in line, I would see their usual deployment as with narrow gaps between each other, maybe 10-12 yards and even narrower or no gaps between the cohorts posted in front. Cohorts in subsequent lines would have smaller or larger gaps according to their anticipated use and relative strength."

Maybe I did not express my opinion clearly enough again. I do not doubt that Caesar (or the Romans of his time) did not have a traditional deployment. I wrote that they did not have to follow this tradition as seems to have been the case in former times, where up to Scipio we see almost no noteworthy variation of the triplex acies according to Hastati-Principes-Triarii. So, a general, especially one with some experience/initiative/imagination could and did come up with many different solutions to address tactical problems and challenges that could be very diverse indeed. Even detracting cohorts from legions was allowed to meet needs, as was evident in Pharsalus. Of course Caesar had a preference for the "traditional" three-line formation but he also made variations.

Now, regarding the freedom of individual legions, these would be as free as their commander in chief would ordain. Most descriptions have a SINGLE battle line/formation being drawn from numerous legions. That clearly suggests that the legions did not have the freedom to conduct their independent little fights along the front. They had an organizational freedom, but still they were designated as wings, center... they had a specific role. Some would have been detached to guard a specific point. See how Caesar orders the third line to engage in Pharsalus? this means that the third line was treated as a whole and not as many independent lines each one belonging to its own legion. When Caesar forms his first line with four cohorts from each legion, he forms a line, he does not form different, independent lines. He also treats them as one, he says they all started the advance, they all stopped to take a breath before the charge... Pompey's legions all kept their place as a whole... Whether these lines have some gaps between cohorts or legions for certain purposes is a different story here.

Caesar makes it clear a few times how legions formed up for battle. here is one example where he tells you straight out how he formed his five legions of infantry into the traditional triplix acies.
"Caesar had three lines, four cohorts out of each of the five legions formed the first line. Three more from each legion followed them, as reserves: and three others were behind these." De Bello Civili, 1: 83

Its the old 4/3/3 formation of cohorts in battle formation.

And where exactly does your disagreement lie? At Pharsalus it seems the formation was 4/3/2/1... Do you really suggest that there were no tactical variations? Afranius posted his legions against Caesar in two lines... Studying a traditional, often used formation is very understandable, not taking into account the different variations is a mistake. (It awfully looks to me like soccer tactics... Whether you play 4-4-2 or 4-3-3, even 5-3-2 etc it is up to the coach. Yet, generally, coaches use variations of the 4-4-2 system.)

Caesar later implies that gaps existed between the legions. He writes repeatedly about battlefields where units are pushed back while others hold.

Did I say that there were no intervals? I said that the commander in chief could decide how large these would have been. It is as though you are debating with yourself Bryan. You are trying to answer to criticism I did not make. Legions would under circumstances fight alone, at others in unison/close cooperation with other legions. You have now new theories previously unmentioned. Up until now, you produced your illustrations and theories as to how the Romans used two lines as a piston to batter he enemy with little squares maniple or cohort sized, and this was quite understandable. Do you mean that these illustrations would only be about a single legion? Now you are debating that the legions did not (ever? traditionally?) fight trying to keep their relative positions but when we read that someone drew his battleline posting legion A&B on the right wing, C&D in the center and E&F on the left wing, we should understand that this someone was preparing to give 6 different battles that would not be coordinated, that legion E would not care where legions D and F were... Now, THIS is a theory you will need much effort to support. Does it also work in your manipular model?

When you say that "gaps would have been necessary", apart from the fact that I also think that certain gaps were employed, which should make you wonder why you again disagree, maybe should make you also understand that you should be more specific. Does your disagreement lie in the width of these gaps? I really cannot understand you. Do you now only talk about the gaps between legions or also about those between maniples and cohorts?

Whole legions run but the Roman line isn't lost. How does this happen when they fight in a continuous battle line? It doesn't. Gaps would have been necessary in battle as well as deploying for battle.

Again I am lost... continuous line? You mean with no gaps whatsoever or with the intention to keep their relative positions as long as possible? Even a hoplite phalanx would not keep straight lines. We have descriptions of how it would take the form of a "snake" while some parts were pushed while others pressed on. Of course this does not mean that cohesion was lost. Each man would think that the men on his flanks were in straight line, but in the run of hundreds of yards, a perfectly straight would not have been kept.

So, now your model has every Roman battle being a sum of many individual, virtually tactically independent battles whose sum would determine the outcome?

Units would separate from each other. Unit integrity is a major psychological factor in battle and it doesn't work if everyone is joined at the hip to the units next to them.

That is a very bold statement. So, in your opinion, every other army, as well as the Romans themselves in later years, did not understand unit psychology? Do you suggest that their insistence that units in a battle-line should keep their relative positions was not a working method of fighting? You know... all regular armies had subunits. So, we do not need units (and here I understand that you do not mean legions but cohorts and maniples again) being detached from each other to "feel" or "act" like units. We could have such models, but we do not have to, as you strongly suggest.

I am officially through with the gap debate. This is entirely too tiring to have to debate the same things over and over again. You win! They fought in a nonstop line.

I am saddened to see that after so many posts you still have not understood my position. Have you actually read what I wrote or did you think it too cumbersome so you had to assume that my position was that the Romans always fought in a long continuous line? I know that my posts sometimes can be too long. I honestly tried to initiate and conduct a fruitful discussion but you do not seem to really want to discuss mechanics or sources but rather to present your opinion. I do not want to "win", I want to think. If you think that a debate only contains a position and a counter position you are mistaken. A debate implies that arguments be exchanged, positions, in a civilized manner, attacked and defended, so obviously more patience is needed than the one you exhibit.

Anyways, one last advice. Give the ancients more credit and think of the possibility that they were actually smart enough to be able to utilize every trick in the bag to achieve victory. When we read A and B in the sources, it does not always mean that A or B is wrong. It might sometimes also be that both are correct.

[Macedon]

All very interesting. Without wishing to distract attention from the main subject of discussion, two things occur to me which might be worthy of mention.

Firstly, although I had never really noticed it before, in the context of this discussion I could not help noticing that Caesar's 80 cohorts would make a nominal ten legion strength but that the average cohort strength was only 250 men, suggesting that each of these cohorts might only contain the equivalent of two maniples, rather than three.Crispvs

Actually, 80 cohorts would regularly form 8 legions, 10 cohorts nominal strength each. This plus one (millarian cohort-double strength) times 480 would make a whole legion. So, a legion would be a little more than 5000 men strong, which makes Caesar's legions be at half strength, 3 centuries instead of 6, 80 man each, the equivalent of 2 maniples instead of 4. I guess that Caesar would have seen to it that at least certain cohorts approached nominal strength. This is actually a very interesting discussion in itself... Would Caesar redistribute his men at will or left the legions with approximately the manpower they had (obviously some very reduced..) We have some mentions of understrength legions, true, but leaving whole legions at perhaps 25% manpower would be a bit too much... On th other hand, tactically redistributing men and contubernia might create problems in the morale and familiarity within the legions, something especially important on the eve of a battle such as Pharsalus. What do you think?

Secondly, I think that , to some extent, it has been assumed that standardised tactics and formations were always employed, but I do not think that this would necessarily be the case, as such regular behaviour would quickly be learned by observant enemy commanders, who would seek to take advantage of it by varying their own tactics to exploit weaknesses that they had identified in the Roman tactics.

I agree. Certain mechanics would have been regularly employed, certain formations studied in paper and in training. It seems that pre-Scipionic manipular legions did not have much freedom, almost always being arrayed in their "traditional" manner, but in the times of Caesar, there seems to have been much more initiative in the initial deployment.

Therefore I agree that it is worth analysing the surviving sources for hints of tactics used, but I think it would be naive to think that they formed up in exactly the same way every time. Therefore I think that it is better to concentrate on exactly how they might have managed to employ those tactics. Thus if one legion supported another, exactly what form might that support have taken? If they could withdraw units from the front line, how this this work?

I agree. this is what I also find more interesting, the mechanics of battle. I made a suggestion as to how the exchange of ranks could have taken place. You can comment on that.

[Sardaukar]

Just to mention, but it'd probably be really rare to have legion to have it's nominal strength. Trend in sources seems to show sometimes even quite substantial understrength, e.g. in Pharsalus where Caesar had to amalgamate 2 legions on left flank (IX and VII (or was it VIII?)).

And quite extreme example was the legion Caesar took with him to Alexandria.

(edited for typos)

[Bryan]

"He gave the command of the left wing to Antonius, of the right to P. Sulla, and of the center to Cn. Domitius: he himself took his post opposite Pompey." 3:89

Shows that command of the line was broken to independent commanders

"...he rapidly drafted a single cohort from each of the legions composing the third line, formed of them a fourth line..." 3:89

"When Caesar perceived this, he gave the signal to his fourth line, which he had formed of the six cohorts." 3:93

Six cohorts, one from each line, means 6 Legions present under Caesar at Pharsalus

"At the same time Caesar ordered his third line to advance, which till then had not been engaged, but had kept their post." 3:94

The third line of the army consisted of two cohorts per legion. The front line was of four cohorts per legion. There was an interval between legions. There is no possible way that the two cohorts of each legion for a total of 12 cohorts for the entire front line could have matched the melee of both Caesar and Pompeius' front line already fighting.

C C C C C C C C C C C C C C C C C C C C C C C C
C
C C C C C C C C C C C C C C C C C C C
C
C C C C C C C C C C C C C
1. 2. 3. C
4. C

1. Command of Marcus Antonius
2. Command of Gnaeus Domitius Calvinus
3. Command of Publius Cornelius Sulla
4. Overall Command and position of Caesar

This

[Gaius Julius Caesar]

Yes after years of campaigning, caesar's army was pretty depleted!
His lines were spread quite thin to match up to Pompey's at Pharsalus!
But he still manage to steal units from his reserves to form the trap for
The opposing cavalry!
Quite a gamble that paid off! He knew his enemy!