The mechanism of Roman line relief

[Patrick Waterson]

I would go with slow and steady rather than hot and hard in most cases, and my impression is that the hastati and principes only fought once each (and that until they had given their all) rather than passing the baton back and forth every so often.

They actually do seem to have used a system of relief by individual maniples before they adopted the line-at-a-time relief system at some point between 437 and 394 BC.

no leg pull at all, and I am studiously trying to not hijack this thread onto an exposition of an alternative model - plenty of time for that in the second half of 2013, I assure you.

I'm simply trying to get those who favour this to look at some of the difficulties with the single line of combat model which this diagram is based upon.


the thing is, the diagram of all those files pushing past each other looks Greek not Roman to me.

It's all precision and mathematically correct fancy drill.

Thanks, Mark.    Mind you, that bit about precision and mathematical correctness sounds very Roman to me!

A Roman way would be to send them off where the rest of the army could see them in action - demonstrating their prowess.  This file based approach as much more in tune with the anonymity of the phalanx.

When we look at the use of deeper formations, there are also some lessons we can see from elsewhere in history.

If they guys in the middle and back cannot see what is going on, then at the first sign of something other than a steady forward march, they are quite prone to wavering and running.

routs always start at the back,

and when men can see an opportunity to get out of a fight with honour, they will take it (helping a wounded comrade being case in pont).

So if you have a formation drill which allows the men in middle and back to take a simple sidestep and avoid becoming the front line - by joining the retreating column - that's a positive encouragement to them to pull out of the fight.

The Greeks / Macedonians countered this with file closers to keep them in place.

But the Romans put their best men in the front as leaders for others to follow.

They also had optios, who could watch the rear.  But having a line of chaps behind with steel in their eyes and hands, plus a code of law which prescribed death for desertion, would have been the main deterrent to early departures.

Further, the Romans introduced more anonymity to their uniforms as the Republic progress, but did not change model of combat drill - which encourages further the potential for men to simply sidestep their turn at the front line.

And there are no file closers at the back to keep an eye on who is joining in, nor to stop the pull back becoming over hasty and precipitating a rout of both formations. 

With a line of combat troops behind, file closers would seem to be an unnecessary luxury.

Interpenetration has always been associated with mutual routing.  Line relief in the horse and musket period was based upon repeated formation changes to enable the formations to pass each other without interpenetrating for that reason (and was considered highly dangerous then too).

And the best way to replace a line was to have it hold its central forward position, have the ends fall in behind that solid centre, and then have the replacing formation march PAST it, and then form out, allowing the damanged line to pull back behind their friends as cover.

Not sure I agree.  As Justin Taylor asked: while all this is going on, what is the enemy doing?

Ultimately, what is described in the diagram just does not look Roman to me.

Probably true.  Of course if relief was conducted by files backing through between files, then the diagram is not Roman anyway.

Much more Roman would be to keep the men in identifiable groups where each man recognises his comrade well enough to call him out for shirking, and have them take turns at having a go, where everyone can see them, and then pulling back afterwards for the next guys turn.

i.e. the gaps are maintained, and they attack as maniples not as a line.

I would have thought that a recipe for piecemeal disaster.  Again, while our lot are cheering on Maniple X, what is the enemy doing?  Taking advantage of his good fortune and our friendly units' separation to chop up Maniple X from three directions or swallow it whole.

So for this notion of files pushing past each other to work – look again at the 4th-6th diagrams in particular for the problem area - remembering that they are 'volunteers' not professionals when this drill was developed, I think a fair bit more detail on how the men are kept in place is required to get it onto any sort of stable footing.

(Oh, and perhaps some sort of indication in the sources that there was a fully continuous battle line would not go amiss)

Livy, Cannae: the Carthaginian veterans 'look like a Roman line of battle'.  Did he mean they had gaps?

Apart from that we have mainly negative evidence: Polybius comparing legion and phalanx mentions no gaps in the legionary frontage; Vegetius drawing up his legion seems to have cohort next to cohort with no gaps in between; Caesar in his accounts gives the impression of solid lines meeting each other, and only at Zama do we seem to have maniples drawn up with spaces in between, this being a deliberate elephant attenuation measure.  In the final phase of Zama, once Scipio has added the principes and triarii to the remaining hastati, the impression is of a single, solid Roman line clashing with a single, solid Carthaginian line.

Keeping the men in place was achieved by discipline and more to the point a penal code that prescribed death for anyone who left his post without permission - including in one case a consul's son when he went out to duel an enemy challenger (and won) without getting permission from the consul.

[aligern]

For the reasons I gave I go with hot and hard. Roman ethos is all about aggression and  there is no point in pacing things if you are the fitter team.

Can anyone remind us of the passage where the Romans are too close to a river to manage their normal line replacement technique. It is most instructive but I cannot remember whether it is in Livy or Polybius.

Roy

[Patrick Waterson]

Polybius II.33.  Even better, here it is: 

Battle with the Insubres.
"The Romans are thought to have shown uncommon skill in this battle; the Tribunes instructing the troops how they were to conduct themselves both collectively and individually. They had learned from former engagements that Gallic tribes were always most formidable at the first onslaught, before their courage was at all damped by a check; and that the swords with which they were furnished, as I have mentioned before, could only give one downward cut with any effect, but that after this the edges got so turned and the blade so bent, that unless they had time to straighten them with their foot against the ground, they could not deliver a second blow. The Tribunes accordingly gave out the spears of the Triarii, who are the last of the three ranks, to the first ranks, or Hastati: and ordering the men to use their swords only, after their spears were done with, they charged the Celts full in front. When the Celts had rendered their swords useless by the first blows delivered on the spears, the Romans close with them, and rendered them quite helpless, by preventing them from raising their hands to strike with their swords, which is their peculiar and only stroke, because their blade has no point. The Romans, on the contrary, having excellent points to their swords, used them not to cut but to thrust: and by thus repeatedly hitting the breasts and faces of the enemy, they eventually killed the greater number of them. And this was due to the foresight of the Tribunes: for the Consul Flaminius is thought to have made a strategic mistake in his arrangements for this battle. By drawing up his men along the very brink of the river, he rendered impossible a manœuvre characteristic of Roman tactics, because he left the lines no room for their deliberate retrograde movements; for if, in the course of the battle, the men had been forced ever so little from their ground, they would have been obliged by this blunder of their leader to throw themselves into the river. However, the valour of the soldiers secured them a brilliant victory, as I have said, and they returned to Rome with abundance of booty of every kind, and of trophies stripped from the enemy."

[Justin Taylor]

If we could take modern football and rugby games as an example of human exertion and hopefully in rugby near combat then we would see that

Indeed but imagine not a few men but hundreds possibly thousands and the tired men either; being replaced or dying.

[aligern]

Wonderful Patrick.  I think that the point that Polybius makes shows that the Romans expect to fall back during the battle in order to accomplish line relief. Hence I hold no truck with the idea that disengaging from an exhausted enemy leaves the Romans open to some dramatic prejudicial move by their opponents.
Roy

[Justin Swanton]

Could I suggest a refinement to the line relief system proposed at the beginning of this thread, as follows (apologies if it makes this a long post). It supposes that the first line of Hastati have been fighting long and hard, are not winning and are in no shape for fancy file-based manoeuvres. They can manage to retire as a body and that is about it. The relief system takes that into account. The positioning of the men should make clear what I'm driving at.

I am working on the assumption that the primary sources tend to favour or at least do not rule out gaps between the Principes' maniples rather than files.

The Hastati are battered and their files are out of kilter.

The Principii move up.

The Hastati begin to collapse in a series of half circles towards the gaps between the Principii.

The half circles gradually shrink as the men retire through the gaps and reform behind the Principii.

The posterior files of the Principii start moving up, narrowing the gaps. The Hastati continue to retire through the gaps.

This process continues.

The gaps are nearly closed. Notice that whilst the Principes files are moving into position, they are covered by the Hastati and do not engage the enemy until they have completed their manoeuvre.

The gaps are nearly closed.

The last few Hastati retire through the nearly closed gaps, covered by a couple of Hastati at the front end.

The last Principes files closes the gaps.

The last of the Hastati filter through the Principes' files and the reconstituted Hastati line moves up to support the embattled Principes.

[Mark G]

I'd love to know how you produced those diagrams - and really hope you dont say powerpoint .

But given the pretty clear statement above that the Romans expected to perform a retrograde movement as part of line relief, I think the weight of evidence is still against this dribbling back of men from the front line and pushing through of men from the second line.

look at the diagram subtitled 'The gaps are nearly closed' and tell me if you were one of the green guys still up front, would you be calmly performing that sort of drill?  or would you - already probably exhausted and certainly stressed from fighting - be more likely to just bolt back to the other green guys in the safe zone?

[Justin Swanton]

I'd love to know how you produced those diagrams - and really hope you dont say powerpoint .

Nope. Freehand 10, though I intend to switch over to Illustrator in the near future as it is the new standard vector design programme.

But given the pretty clear statement above that the Romans expected to perform a retrograde movement as part of line relief, I think the weight of evidence is still against this dribbling back of men from the front line and pushing through of men from the second line.

One could understand the retrograde movement as follows: the Hastati fall back on the Principes who themselves don't move. The Triarii behind them then retreat several yards back to make space for the Hastati as they retire through the Principes' gaps and reform behind them.

look at the diagram subtitled 'The gaps are nearly closed' and tell me if you were one of the green guys still up front, would you be calmly performing that sort of drill?  or would you - already probably exhausted and certainly stressed from fighting - be more likely to just bolt back to the other green guys in the safe zone?

I think it might something in between parade ground precision and the anarchy of panicked flight. The Hastati are battered but intact. They feel they are getting bettered by the enemy but have not reached the point where they feel they are about to be overwhelmed by them. Withdrawal is a bit of a scramble but fairly orderly. The front-line troops, who have not broken, continue to face the enemy, keeping heart as they back slowly towards the gaps and safety. No reason for anyone to have the heebie-jeebies, drop everything and run.

Experienced troops know that if you panic you are probably dead. Safety is in keeping line with your comrades. This is reinforced here where safety lies precisely in doing that.

[Erpingham]

One could understand the retrograde movement as follows: the Hastati fall back on the Principes who themselves don't move. The Triarii behind them then retreat several yards back to make space for the Hastati as they retire through the Principes' gaps and reform behind them.

Why not just line up the triarii further back to start with?  IIRC Vegetius has the standards and command between lines 2 & 3 and also rallies the velites there after they have fallen back, so you'd want some space available anyway.

Experienced troops know that if you panic you are probably dead.

Indeed, but this drill is supposed to work with a bunch of militia with a few weeks basic, as well as experienced troops.

[Justin Swanton]

One could understand the retrograde movement as follows: the Hastati fall back on the Principes who themselves don't move. The Triarii behind them then retreat several yards back to make space for the Hastati as they retire through the Principes' gaps and reform behind them.

Why not just line up the triarii further back to start with?  IIRC Vegetius has the standards and command between lines 2 & 3 and also rallies the velites there after they have fallen back, so you'd want some space available anyway.

The question then is what were the 'deliberate retrograde movements' mentioned by Polybius? What mechanism of line relief would require them?

Experienced troops know that if you panic you are probably dead.

Indeed, but this drill is supposed to work with a bunch of militia with a few weeks basic, as well as experienced troops.

I suspect the training was a bit more thorough than that, otherwise the troops would be incapable of any kind of manoeuvre in the heat of battle. Mixing experienced troops with greenhorns would also have the effect of stiffening the greenhorns, who would feel confident around the veterans' constancy, besides feeling ashamed of running when the veterans did not (plus the fact they would executed out of hand for doing so).

[Erpingham]

The question then is what were the 'deliberate retrograde movements' mentioned by Polybius? What mechanism of line relief would require them?

Speculating, because I don't know what the Latin says, but if the army had concertina-ed to reduce the gaps between the three lines, the retrograde movement of the front line through the second would be impossible, because there wouldn't be enough space between 2 and 3.

[aligern]

My worry about the attractive diagrams is one of basic philosophy of how warfare works in this period. To me it is vitally important that troops maintain order and cohesion and that the right people are in the right place all the time. Thus a Roman unit cannot just turn around and fight because the men whoa are meant to be at the front will now be at the back. Those who are meant to be a t the frbont of a unit have to be in that posit ion a he n they fight. They right. Marker ha s to Ben the right marker because he knows his role in a drill movement,.
So I don't see the Hastati retiring by filtering through a gap, losing order in the process. Caesar makes a point at the Sambre that his men have lost order and cannot fight effectively. Turning to right or left and then queuing to get through a gap introduces a fundamental disorder and the tr oops will be crushed together, unable to fight and prone to panic.
I would go with the Hastati stepping back, turning on a signal and dropping back through the Principes who advance to intimidate the enemy into holding back as the fall back manoeuvre is conducted.  Having dropped back the Hastati turn again and then all the right people are in the right places.
Order is everything when fighting relies upon teamwork.

Roy

[Patrick Waterson]

I would not categorise the Romans of the Republican period as a 'bunch of militia'.  Polybius, although sadly saying little about Roman techniques on the battlefield, indicates that they had good low-level officering (as has been pointed out earlier in this thread ) and also describes their system for duties in camp, which shows a level of familiarisation and sophistication well above that of the average feudal 40-day levy.

While it is quite likely that some legions did get only a few weeks training (the mass of recruits in the Cannae campaign being a case in point) these few weeks were probably quite intensive.  We might also remember that the average British Territorial Army soldier gets about six weeks' training (equivalent) per year, and this in theory makes him the equivalent of a regular soldier (at least the MoD think so).

Quality of training seems to be at least as important as quantity.

Polybius' 'retrograde movements' (the Greek has epi poda, which specifically means 'retreating backwards') must perforce involve the first line retreating behind the second line into the space between that and the third (so far so good), but as Polybius implies any retirement would have landed the Romans in the soup (or at least the river), we must conclude that the first line continued to retire behind the third - i.e. through the principes and triarii, taking post behind the triarii.

Patrick

[Justin Swanton]

Polybius' 'retrograde movements' (the Greek has epi poda, which specifically means 'retreating backwards') must perforce involve the first line retreating behind the second line into the space between that and the third (so far so good), but as Polybius implies any retirement would have landed the Romans in the soup (or at least the river), we must conclude that the first line continued to retire behind the third - i.e. through the principes and triarii, taking post behind the triarii.

Patrick

Which is different from Livy's legion, where the Hastati stay in support of the Principes (or have I misunderstood Livy's reference?)

[Patrick Waterson]

Well spotted and perfectly understood.  Livy says:

"...tum principum pugna erat; hastati sequabantur."  (Literally: 'Then the fight was of the principes; the hastati followed [them].)

It is hard to see how this could mean anything other than the hastati staying behind the principes, presumably as supports (moral and/or actual).  In Livy's legion the hastati and principes are also reinforced, apparently piecemeal, by the rorarii during the course of the battle (a relic of the earlier piecemeal commitment system for propping up the line).  The Polybian legion lacks rorarii (or, more accurately, the men who might earlier have been rorarii are now incorporated directly into the first two lines).