The mechanism of Roman line relief

[Justin Swanton]

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 forgot to mention: please feel free to propose any alternative model you like. Mine is just a hypothesis after all.

As Threadmaster (or Judge Thredd?) my only provisio is that you supply brightly coloured diagrams  .

[Erpingham]

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). 

Which is what we would expect (or I would).  Seems to me there are two parts to the line relief thing.  An exchange of lines 1 & 2 was probably fairly routine.  Roy has suggested the hastati would have gone into action expecting to exhaust themselves and be relieved.  Even if this wasn't the case, I'd suggest that exchanging the first two lines fits with an expectation of fighting on and winning.  If it "came to the triarii" they were in a tough place and the idea was a ordered withdrawal.  In the later Republican legion though (e.g. Caesar), without the lines being of different types, does this change?

[Justin Swanton]

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). 

Which is what we would expect (or I would).  Seems to me there are two parts to the line relief thing.  An exchange of lines 1 & 2 was probably fairly routine.  Roy has suggested the hastati would have gone into action expecting to exhaust themselves and be relieved.  Even if this wasn't the case, I'd suggest that exchanging the first two lines fits with an expectation of fighting on and winning.  If it "came to the triarii" they were in a tough place and the idea was a ordered withdrawal.  In the later Republican legion though (e.g. Caesar), without the lines being of different types, does this change?

Of course. If things went badly the Hastati and Principes would retire through the kneeling (and immobile) Triarii and retreat to the camp. In this case they would have gone straight into the river.

Talk about me missing the obvious  .

[Mark G]

On that point, are their any actual examples of the Romans WITHDRAWING behind the triarii?

i.e. the Triarii acting as a defensive force to cover a retreat?

I can only think of examples of the Trairii being committed as a mass-de-decision to win the battle now that the enemy has been exhausted.

(Goldsworthy and Sabin offer a compelling counter model for you to look at, they do not have the single formed line of battle, which I think is where all the problems with your attempt start from)

[Justin Swanton]

On that point, are their any actual examples of the Romans WITHDRAWING behind the triarii?

i.e. the Triarii acting as a defensive force to cover a retreat?

I can only think of examples of the Trairii being committed as a mass-de-decision to win the battle now that the enemy has been exhausted.

(Goldsworthy and Sabin offer a compelling counter model for you to look at, they do not have the single formed line of battle, which I think is where all the problems with your attempt start from)

I imagine Livy is clear enough:

[10] The triarii knelt beneath their banners, with the left leg advanced, having their shields leaning against their shoulders and their spears thrust into the ground and pointing obliquely upwards, as if their battle—line were fortified with a bristling palisade. [11] if the principes, too, were unsuccessful in their fight, they fell back slowly from the battle—line on the triarii. (From this arose the adage, "to have come to the triarii," when things are going badly.) [12] The triarii, rising up after they had received the principes and hastati into the intervals between their companies [ordinum], would at once draw their companies [ordinibus] together and close the lanes, as it were; then, with no more reserves behind to count on, they would charge the enemy in one compact array.

Here they represent a safe haven for the exhausted Hastati and Principii, besides being a last-ditch attempt to win a lost battle.

It is difficult to imagine fighting the enemy in anything else than a solid line. A soldier has to have both his sides covered as he is fully occupied fighting the chap in front of him. If he is exposed on one side or the other, as would be the case with a gap-punctuated line, he is dead.

[Justin Swanton]

(Goldsworthy and Sabin offer a compelling counter model for you to look at, they do not have the single formed line of battle, which I think is where all the problems with your attempt start from)

Do you want to give a summary here?

[aligern]

Ahha the vulnerability of the gap punctuated line raises its head.  I remember that this has been debated in the past and that the opponet does not rush into the gaps because he must break formation to do so and the gaps are covered off by  Velites or Prncipes or hastati as appropriate.  It seems attarctive to wargamers to say that the flanks of the fighting units are vulnerable, but actually no enemy is going to lose cohesion in an attempt to exploit them because this breaks his line and exposes his tactical flanks as those advancing into the gaps turn to fight the flanked troops.
Roy

[Patrick Waterson]

All I would say to this is: if a fractured line was ostensibly so versatile and effective, why then did everyone else before, during and after the Roman period fight with continuous lines*?

(*A mild caveat here: the later Renaissance saw the tercio - an infantry 'moving fortress' that did not form a continuous line with its neighbours - becomes the premier infantry formation on the battlefield.  However the tercio was rendered obsolete by Swedish continuous-line infantry, so I think the basic point still stands.  We also have French columns during the Napoleonic Wars: these were not as a rule deployed in a continuous line, and although successful against shaken continental troops tended to receive a bloody nose against British infantry - who took advantage of their vulnerable flanks ...)

Patrick

[Mark G]

when you say everyone, Patrick, what evidence do you have for this?

Cause the only solid stuff I can find is that Hoplites did when fighting as one city state - but even the bigger hoplite battles broke into smaller sub phalanxes.

The Macedoninan phalanx does seem to have been broken up into separated phalanxes at a tactical level too.

Once you get a decent number of men into the front line, its impossible to move them in a solid continous line.

[Mark G]

<p> Do you want to give a summary here? </p>

not really.

A, its a different topic entirely.

B, I have a ton of stuff on it going into Slingshot over 2013, and it would do an injustice to that work to preface it here.

[Duncan Head]

(*A mild caveat here: the later Renaissance saw the tercio - an infantry 'moving fortress' that did not form a continuous line with its neighbours - becomes the premier infantry formation on the battlefield.  However the tercio was rendered obsolete by Swedish continuous-line infantry, so I think the basic point still stands.

The Swedes - and perhaps even more so, the Dutch battalions before them - were not continuous lines, but formed in chequerboard formations very similar to the popular conception of the Romans. (See http://tinyurl.com/cucsk4p, for example.)

While that example may be irrelevant because of firearms, the Tang writings of Li Jing recommend two lines of dui (fifty-man "centuries") in a loose chequerboard - http://tinyurl.com/bqqe2kw.

[aligern]

 Your examples are pertinent despite them being  based on firearms. Late XVIth and early XVIIth century battles often became hand to hand affairs with the shooting having been used to weaken the opponent.  At the Dunes the Cromwellian soldiers chargev in with pike and with musket swinging!!
Roy

[Mark G]

to add some colour to this.

I have friends who do sword fighting (not fencing, but the meaty stuff that means that they have to call the Police before they go to training because they are carrying proper weapons).

they all tell me that this is the best sword fight on film.

http://www.youtube.com/watch?v=gHCvV8uUr9U

its 6 minutes long, and both guys are knackered half way through.

Whimpy actors and over weight renactors not withstanding, it makes the point that men will pull back mid way through a fight time and again and still be fighting.

[Erpingham]

It is difficult to imagine fighting the enemy in anything else than a solid line. A soldier has to have both his sides covered as he is fully occupied fighting the chap in front of him. If he is exposed on one side or the other, as would be the case with a gap-punctuated line, he is dead.

I think this has been picked up pretty well by Mark but the general point of who flanks who is that anyone who rushes into a gap left by design between two units is in greater danger because the gap-leaver is prepared to have the enemy to the flank, rather than it being an impetuous decision. 
On the non-continuous line, on Ancmed Steven James pointed out that Vegetius mentions a Roman formation called the saw (serra ?), which Steven envisages as two lines with gaps offset so the rear rank is behind the gaps in the first.  Such a formation could exchange lines simply by the front rank reversing through the gaps, leaving the second line to become the "teeth".  Just another one to throw into the mix

[Patrick Waterson]

when you say everyone, Patrick, what evidence do you have for this?

Biblical cultures, judging by battle descriptions and available reliefs, used solid lines which could part to emit and perhaps admit mounted forces.  This process is detailed as being used by Gauls in Lucian's 'Zeuxis and Antiochus', aka 'Elephant Victory'.  In classical battles the one case of serious gapping (First Mantinea) in classical sources (Thucydides) has the 'gapped' part of the line overwhelmed by its cohesive opponents.  I have yet to see a description of a phalanx (hoplite or Macedonian style) advancing by choice in anything but a continuous line except when Xenophon details his men into separate 100-man units for mountain fighting.  Greek and Roman accounts of fighting barbarians do not seem to mention gaps between their own subunits or those of the enemy (if anyone has any that do, please mention them).

Saxon battles tended to be fought in 'shieldwall', which is not really a formation permitting any gaps.  Mediaeval actions seem to involve solid masses of men.  Swiss did indeed have gaps between their keil, but the keil themselves were big solid blocks of pikemen and/or halberdiers.  Tercios were similar: big units which deployed with intervals between them.  One reason for the intervals was, as Duncan hints, that firearms were now part of the repertoire: the tercio had all-round shooting capability.  It also packed a massive close-ranked punch in melee.  Where it fell down was when it was matched against the nimbler Swedish formations, which emphasised a more linear and connected approach.  Duncan rightly points out the Swedes had a staggered line of battle, though it is noteworthy that in the English Civil War, when tercios were no longer the Swedish system's opponents, it was back to complete lines.

18th century military theorists looking for ways to rise above the linear (continuous line) firefight went back to thinking about large, deep and semi-independent pike-armed formations.  These never saw the light of day but had a cultural successor in the French column - which foundered against any effective linear defence, so that in the 19th century everyone in Christian Europe except the Russians went back to the linear firefight (the Russians caught up later, after the Crimean War).

The overall verdict of history seems to be that it is better to stay together in a cohesive formation.  Some armies could operate with intervals because their units could give each other effective mutual support against the type of opponents they were fighting, but these seem to have been a few big units rather than a lot of small ones.  Swiss in particular used skirmishers and momentum to avoid giving their opponents easy access to their flanks - and were good at all-round defence if the opponent did get there.

Li Jing's Chinese infantry drilled in a loose chequerboard formation, but deployed for battle "in two lines or echelons of equal strength," without specifying whether these were solid or chequerboard type lines.

However, as Anthony mentions, sometimes a specially-created gap can suck in opponents as part of a cunning plan, a sort of Cannae in miniature.  I seem to remember seeing somewhere a description of a Byzantine manoeuvre of this nature involving a whole meros: the unit would deploy as a three-sided box with the open side (facing the enemy) covered by a thin screen of troops.  When the enemy attacked the screen would fall back, dragging the enemy into the trap.  Whether this trick was actually used in battle I know not, but the idea was there.

Patrick
P.S. - The swordfight is much as one would expect from unshielded barbarians with no stamina and an excess of enthusiasm.  Trained Romans would have polished off either of those two quite quickly by taking the first flurry of blows on the shield and then delivering a good stab, which would have been no more exhausting than presenting arms.  Bring on the next Celt!