On the checkerboard formation

[pezhetairoi]

How did the Romans actually replace the hastati with the principes? Wouldn't the gaps left between the maniples actually mean the barbarian enemy could just swarm into the gaps and outflank every maniple instantly and hit them from three sides if not all four at once, if the principes were not immediately behind the hastati? Did the hastati open up into a full line to fight before closing up into a block to withdraw through the gaps in the principes' line? And that raises the question of their vulnerability when opening and closing. Any input? It's a question that has been plaguing me to no end.

[TWFanatic]

Good question. Very good question. Unfortunately I don't know the answer, so I'll have to wait with you.

[Spoofa]

I think they've talked about this before, they dont know exactly how it worked.

[Sand]

Im not an expert by any means but I understand that the reason enemies did not flood through gaps between the maniples was because of the style of warfare the Romans encountered and practised.

Fighting in armour, carrying a shield and weapons was extremely tiring physically and draining emotionally - It must have taken hours to butcher the Romans at Cannae after they devolved into a mob. It was also quite a challenge to persuade citizen levies [Roman troops in the early Republic were farmers, not professional soldiers though obviously experience came with time] to risk charge into a mass of enemy, and vice versa.

Because of the above combat was not a single charge and melee, but an extended bout of skirmishing [hence all the missile weapons carried by Roman, Carthaginian and barbarian troops], rallying by the officers to charge, a short bout of melee, and then parting to rest whilst rallying for the next charge. Victory came when one side or the other was exhausted or disheartened and turned to flee. Then the mass of casualties would occur.

The army that could feed in rested men, with aggressive leadership tended to carry the day. The Roman system allowed them to pull back the first line and advance the second in good order and Roman commanders practically by default were extremely aggressive. The Roman system seems odd but it was suited to the type of warfare the Romans encountered - skirmishing/short spells of melee where morale and stamina were decisive factors. At least, thats my understanding of it.

[The Internet]

With the enemy they faced (barbarians mainly) they faced an enemy that charged in groups (tribal groups mainly) so the Romans never had to deal with their entire front line being over-run. To deal with these tribal groups they had their own "groups" to combat them (their groups obviously being the maniples of hastati and principes) and then they added their own twist on it by giving the army a system where they were able to rotate and refresh the front ranks to keep the frontline fresh, unlike the barbarians who got tired out and over-powered.


Thats my take on their military layout anyway, it can never really be confirmed or denied unfortunately.

[KuKulzA]

fortunately in my Aedui campaign i have some veteran gaesatae, botroas, gaeroas in an army so I usually just... charge...
shock and awe tactics... an army of naked ferocious barbarians chargin down on you Camillian farmers...

but rambling aside I think Sand is right. Also, the Greeks and Phoenicians tended to fight in conventional field combat with front ranks advancing, etc. so the Romans being able to rotate fresh men would allow them to constantly pit fresh troops against gradually tiring hoplite-types

[pezhetairoi]

Yeah, I could see the sense in the Roman formation against the Greek, because the Romans only fought on segments of the line but the Greeks couldn't exploit the gaps in between since they were largely phalangites and to do so would have broken their formation. But the barbarians... Surely they did not always charge in small tribal groups? If what we are looking at is a thirst for glory, loot, renown, etc, then once the first courageous groups starting running forward, wouldn't the rest also have gone forward, not wanting to be see to be hanging back?

Furthermore, as devil's advocate, let me offer a weakness to the short bouts of warfare point: Granted that such was the style of warfare in those days, it does not seem that the enemy would have stood by while the Roman brought up fresh troops. Their chiefs would have been able to see that for what it meant, and would have done his best to disrupt the passage of lines by possibly charging, even if his soldiers were out of juice, in an effort to catch the hastati and principes while they were still passing through, and induce confusion.

I realise there probably isn't an answer to this, but let's see how creative we can get with the answers :) Since the experts don't know either, the truth is fair game for us people. Let's postulate.

[KuKulzA]

I think the maniple tactic is perfect for long frontal attacks, since it rotates fresher and more experienced troops regularly and many soldiers are equipped with javelins to whittle down enemy numbers and morale. But if a Gallic chieftain had all his warriors charge at once and got the cavalry attacking their flanks... I mean that kinda throws the whole frontal engagement system off balance...

I mean in general those Celts were good warriors... taller, muscular, with longer swords and spears and fearsome and confident...
from what I understand the Romans had the efficiency going for them... the shorter swords and large shields and rotation of troops allowed them to be efficient and almost mechanical in a sense... very disciplined... but seemingly very linear

i mean you look at times when others have been victories against early Rome, they usually disorganized the tactic with flanking or a very determined charge with a lot of momentum....


just some thoughts

[Comemnus]

Sand is mostly correct. This is why centurions were so important because they were the ones that led the assaults, they were the ones who worked their men's courage up to actually fight, they were also the ones to have th highest mortality rate in the entire legion for just these reasons. Much of a n ancient battle was the two sides facing at each other and trying to work up the courage to come to grips.

also you have to realize that if the Roman's enemies moved into the gap between he maniples they would be flaked too wouldn't they , then it would be just like a zipper... a zipper of doom.

[micasa]

I don't know anything about the real Roman world but in the EB Roman world I've noticed a couple of things:

Using the checkerboard formation:

I put the Hastati in front with a row of Heavy Hellenic Skirmishers behind with their skirmish ability deactivated. When the enemy charges the Hastati toss their pila, then as the enemy closes with the Hastati the Skirmishers toss their javelins. From what I've seen you're correct. The enemy formations tend to wrap around my Hastati formations but that allows the Skirmishers to keep tossing javelins at their now exposed flanks and rears. Lots of casualties. Also, the Hastati bear the initial brunt of the enemy charge. If the enemy squads have not yet fled by this stage then a swift charge by the third line, my Principes, usually deals the death blow. Any attempt to flank me brings my fourth line into play, the Triarii. Sometimes I let the enemy's flanking troops actually charge my units from the flank before I charge them in turn with my Triarii, depending on the morale of my troops being charged.

This sum of tactics has worked well for me against the Arverni and Aedui.

The Maniple system:

I'm using this to fight the Hellenic tribes. A solid line of Hastati set to Gaurd Mode. It means they hold formation and don't tire as the enemy units charge into them and hack away at them. Casualties are also limited to a large extent. I also line up Hellenic Heavy Skirmishers in the second row to toss their javelins at the enemy. But, with a solid line of Hastati in front, once the enemy closes with my front line, you have to manually tell each Skirmisher unit to toss their javelins at the now closed enemy ranks. I hold that formation for quite some time (the Hellenes tend to be hardier following the initial charge than the Celtic units) until they're tired, very tired or exhausted and usually by then my Skirmishers are out of javelins. At this stage I divide my Principes line in half and send each one around the flanks, move my Triarii forward to fill any gaps made by fleeing Hastati and, when my Principes are in position, charge my Skirmishers straight forward through the Hastati lines for melee combat. Then the Principes close in around the sides. Even Thorakitai generally crumble at this point and try to flee. The bonus with this tactic is that, with generally few cavalry in my Roman formations when fighting Hellenic units, I've almost surrounded the enemy army. As they flee the casualties mount rapidly.

Both of these strategies rely on the enemy attacking me.

When I attack I divide my army into three Cohorts (for lack of a better word and it sounds cool):
In the centre I keep my Hastati backed by Skirmishers. Usually 5 to 6 squads of Hastati with an equal number of Skirmishers. Hastati are set to Guard Mode.

On my left flank, in box formation i.e., formation 3 (two Principes in front with two behind) four Principe squads separate from behind my Hastati and Skirmishers once I have approached the enemy formation. I halt the Hastati and Skirmishers and move the Principes around the left. (The enemy usually places its cavalry on my left flank and the Principes have a bonus fighting cavalry an I also want to keep my strongest units for the right flank). They move beyond the line of Hastati and Skirmishers to flank the enemy line and stop only when they draw parallel with the forward enemy line. Likewise, my box formation Triarii move around the right flank. If the enemy hasn't yet turned to meet my flanking Cohorts then I select my Hastati and double-click a spot somewhere behind the enemy formation. My Hastati are in Guard Mode so they run forward until they bump into the nearest enemy squad, halt, form up and only the front row of each Hastati squad hacks away at the enemy. All I'm trying to do with the Hastati at this stage is tie the enemy units down and stop them from turning to attack my flanks.

If the enemy line has turned to meet my flanking units then I take the Hastati off Guard Mode and charge them into the now flanked enemy units. Usually the enemy doesn't turn though.

With the Hastati engaged I charge my Skirmishers forward until they are directly behind the Hastati and order them to throw their javelins at the strongest of the enemy units. Then I take the firts two Principe squads and charge them into the flanks. Same with the Triarii. I now have four units in reserve, two on each flank, and when my Skirmishers run out of javelins I charge them into the fray with the Hastati. If the enemy formation is still fighting at this stage I charge the two remaining Principes and Triarii squads into the fight and remove the roginal two from each Cohort to give them a breather.

I ensure at all times, when attacking or defending, that my squads are Fresh before they charge. No matter how far I've had to march and how much time it took, possibly leaving very little time for the actual battle, I always ensure that my troops are well rested before the charge. Even if I run out of time before the battle concludes I know that my units are probably not going to rout and therefore be cut down in large numbers as they flee. Sustaining heavy casualties while trying to prosecute a war far from home is the death knell of any campaign and will set you back multiple seasons and even years as you try to rebuild your army. But that's a strategic map issue...

[pezhetairoi]

Interesting, that. The insecurities I perceived in the checkerboard formation and the limited frontage of the system meant that I never actually used it. I created 4-unit divisions instead, cohorts of a sort, with 3 up and 1 back as reserve or to shore up a line if attrition was getting the better of it. Gladly to say at least, I never have problems replenishing my troops even when far away, because I have a constant stream of reinforcements going up :D Just a year or two back I was in the Polybian era, with 3 fullstack legions up north deep inside Sweboz territory annihilating them. Every turn or so the army would face one or more Sweboz fullstacks, but at least 2 of the 3 would be attacking at any one time on the front line. Any legion losing more than 20% is withdrawn one turn's travel back, and given the attention of the reinforcement vexillariums that follow each army, whose numbers vary every now and then, so I never lost momentum, I'm proud to say.

That's ended now, though. Marian reforms have happened, now I can retrain almost anywhere! Ironically the only time my campaign was put completely on hold was when I had to convert my Polybian legions to Marian. XD Big mistake though, because they took advantage of it and churned out another 3 fullstacks. Darn.

But back to the checkerboard topic. I'm starting to see the benefits of it now, I don't think I gave the piecemeal thing enough credit. I suppose you're right, the checkerboard system -does- work, assuming the first rank of the principes are right flush with the last rank of the hastati.

But now, one more question: How do the triarii come up? And if the hastati retreat past the principes to rest, wouldn't that mean they would have to withdraw completely off the main line of resistance? That would mean the flankers of the principe maniples would no longer have a threat of being outflanked themselves, and in fact, they could even lap around to the -rear- of the maniples, since the back door is now opened. Unless, of course, the triarii somehow came up. Did they pass -through- the hastati maniples? Or did they do some elegant sidestep so they were directly behind the principes, and time it just right so they sidestepped back into place where the hastati would have been, closing the backdoors in the principe line?

If the latter, it does seem an awful lot of synchronisation for the chaos, noise, confusion and complete exhaustion of the ancient battlefield, and hence to me doesn't seem very plausible, especially for what is essentially a citizen army that does not train all year round.

In fact, another question: Did Roman citizens get any compulsory training periods on the Campus Martis every year or something, to refresh or educate them in the tactics of the triplex acies? Or were they trained on the job, only when they were called up for campaign, before they set off?

[Maeran]

As I understand it, most of the training was done by more experienced soldiers on the march.

Personally, I chop and change tactics depending on what I expect the enemy to do.

If I'm up against a barbarian army that I expect to do an all out charge, I form a solid line of Hastati with Principes behind in something resembling the checkerboard of the quincunx formation (the Triarii ar behind that but only get used if the enemy throw their general into the fray). If the Hastati and cavalry cannot get the barbarian hordes running for the hills, or it looks like the Hastati will fail anywhere, I order my Principe's to attack, and withdraw my Hastati after the Principes are engaged. This isn't historical, but it's the closest I can get I think, since the game engine doesn't do the long series of charges and rallies that really happened.

With the dumb, dumb Hellenic factions, I can be certain that my skirmishers, or just the stupid AI will split the phalanx line up, so I use a more textbook version of the formation as mentioned earlier.

[Sand]

Regarding compulsory training, I dont believe so. Most Roman campaigns opened with a series of military disasters in which their levies were shown up for what they were - amateurs. Most training seems to have occured in service, on the campaign and the better Roman generals tended to delay active combat in favour of extended training, like Scipio who spent a year in Sicily training for the invasion of Africa. By the end of the 2nd Punic War many Roman soldiers had been in service for well over a decade [ The poor survivors from Cannae served until the end of the war, and some even longer] and their legions were at least a match for any proffessional hellenistic force. This doesnt appear to have been maintained during peacetime and the insecurity that military blunders caused appears to have contributed to the final decision to crush Carthage.

That said, they supplied their own gear so they would have some basic familiarity with it.

As to the triarrii, I understand that they would act as a rallying point for troops from the first line to fall back behind and rest, while the second line engaged the enemy. How the first line came through the triarii without chaos, not sure - probably there was a simple rule like "Always move through the gap to your left". Its also possible that when out of contact with the enemy that they just streamed through the ranks.

The Romans had a relatively large number of leaders attached to each unit [Apparently related to a good healthy republican distrust of concentrating power in one man - the rotation of command between three pairs of Tribunes seems weird, but it appears to have worked for them] right down to two centurions for each maniple so long as the maneuveres were relatively simple Im fairly sure it could have been pulled off given the strict discipline that was instilled.

As to who would cover the gaps for the second line - Id assume the velites would do so or the triarrii would move up. But either way, by Roman reasoning, at this point either the second line is busy slaughtering an exhausted and shaken enemy [so they wont be in any shape to exploit gaps], or the Legion is in serious trouble anyway.

[geala]

Indeed nobody knows for sure how they did it, and here I have read some very good ideas.

My imagination is that the hastati and principes were in a relatively loose order, with a space for a soldier of about 1,80 m. The two centuries of the maniple advance one behind the other, so they can manoeuver easily and avoid hindrances (unlike a phalanx). The centuries of the principes were normally behind the gaps between the hastati maniples, if not exceptionally (like at Zama) they were behind the hastati.

Before the attack and after the velites returned the rear hastati century can turn and march in the gap, if a closed front line is desired. In one of the pauses of the fight they can turn and march behind to allow the principes to come to the front. Or, perhaps the safer version, the soldiers can shorten the distance between each other (from 1,80 to 0,90 m), with one side as the base, which will create century wide gaps in the front. Instead of turns and backmarching (difficult) only sidesteps were necessary. To have different spaces for the soldiers for different situations was also a method for the Greek phalanges.

Another possibility is that the centuries were beneath each other from the beginning and the legio fights with gaps in the front line. I don't have such a good feeling with this, but I know that some excellent scholars prefer this version.

I don't believe that the individual rows were changing during the fight (like in "Rome", part one) or the first rows were attacking repeatedly. To move like this in the thick of fray would have been very dangerous for the order and prone to disaster.

[Roy1991]

Wouldn't the gaps left between the maniples actually mean the barbarian enemy could just swarm into the gaps and outflank every maniple instantly and hit them from three sides if not all four at once, if the principes were not immediately behind the hastati?

That works both ways though, because if an enemy entered those gaps, the Romans could hit them from 3 sides too. I imagine a barrage of pila coming from 3 different sides would be quite devastating

[pezhetairoi]

But they'd eventually run out of pila, then things would get fun... A maniple had a frontage of 20 men, which at about 1.2m per man makes 24m per maniple. The gap would also be about 24m. That's quite a large gap for people to be pouring through, I'll give you that...

Really good ideas here, I'm glad my question has gotten people thinking. The sidestep seems to me a reasonable assumption with regards to the fighting... If only we could get a bunch of reenactors to wargame this.

[CaesarAugustus]

Interesting thoughts on the checkerboard formation I must use this more often.... Hellenic commanders must have gone through hell trying to fight the more manuverable Roman formations.

Something I've always wondered is why Roman commanders held back the Triarii. Its seems wasteful to allow your "green" troops to be slaughtered and only sending in your more experienced troops when absolutely necessary. (I understand the importance of reserves, of course, by why hold all of your best troops in the back lines?)

[pezhetairoi]

The triarii lines were only half the size of either the hastati line and principes, so they wouldn't have been able to make that much of a difference either. They were veterans, the equivalent of the evocati, and given that they had survived, as citizen levies, for numerous years of campaigning here or there, I suppose they had done their share of dying. Time to let the younger ones get some experience. You want to ensure you always have a pool of triarii to draw from. Also, battlefield courage gains social honour and stuff. I suppose you could argue it's so the younger ones (especially the hastati, who tend to be the youngest) get a chance to prove themselves in battle and win honours that would increase their social standing. The triarii, once again, have gotten their share in their time. But that's probably a small reason compared to other tactical considerations.

And I would suppose they didn't -hold- the triarii back per se. Once they cycled through the hastati and principes, it would have gone to the triarii. Probably, most of the time the battle was won before it came down to the triarii, so it would appear to us that the triarii were rarely used.

Furthermore, the keeping of the experienced troops for last was quite a sound consideration. After the shaken hastati and principes have retreated, and the battle is going pear-shaped, and everyone is shagged out and can't think very well anymore, you want some solid, dependable old guys to laugh at you and say, 'Hah! Running already? We'll show you what fighting is really all about!' and march forward to meet the enemy with chin held high while you stand there catching your breath, thinking 'Damn, they're really cool. Once I get my breath back I'll join them.'

Whereas if you placed the triarii in the first line and waited for them to get tired and shaken to withdraw, things would get worse. People would see the best of the army withdrawing through the gaps, with the exhausted wild-eyed look, and the older men would be going 'damn, these are real tough guys. Good fight, eh? But damn, they are tough.' Sure it would take longer for them to retreat than the hastati, for example, but they eventually would, and then you'd have the hastati and principes thinking 'damn, if even they are down, what about me?' There would be some psychological effect no matter how small. And that could grow because the triarii retreat already would give them some expectations of the enemy's prowess, perhaps exaggerated. When they go up there into the front line, surely their fears would magnify themselves. In the second line you can't really see that much and the unknown tends to make reality, when it comes, all the more frightening and disorienting. Already battle was mostly spent getting up courage. How much harder it must be to attack a bunch that have already beaten the best troops in your formation, and how much a harder job it would be for the centurions to motivate their men in the mroeale equivalent of an uphill charge.

One thing at least was that Roman consuls showed no qualms about using triarii when the time came to use them, when they were cycled to the front. Compare that to Napoleon millenia later, who lost or could not complete his victories because he kept his Garde Imperiale and refused to use them when the moment arrived, due to some mindless cherishing of them. When you keep the experienced troops for last, there are two ways it can go: if you're not afraid to use them, as and when you use them, it becomes a morale booster. Of course, it could be disastrous if those are defeated since everyone will be demoralised, but in the short term it makes everyone fight all the harder. And anyway, if you are using them in the first place, that means you're already making your last throw so if the elite lost, it wouldn't really matter if the army was demoralised anyway.

But if like Napoleon you DO refuse to use them, it hurts the army as a whole because you'd have the hastati and principes fighting and dying by droves while you're holding back the best troops, all concentrated in one formation that is never used, who in this situation would have been better used parcelled out among the frontline to stiffen the formation. The Roman legion followed the former mindset so it was really not all that bad. It wasn't particularly wasteful either, remember the imbalanced casualty rates of ancient battles. You didn't actually have -that- many people dying on the winning side. The hastati and principes normally retreated because of exhaustion, not because of casualties.

The Romans held back ALL their best troops in the rear lines because to send them all forward at once (and send them forward they did) would be an extremely visible and very powerful morale booster. To use less of them and only in certain segments of the line instead of all along it would lead to morale issues along certain areas. For them, it was a case of 'saving the best for last' rather than a fetish for collecting the whole set of triarii and keeping them elite and untouched like the Persian Immortals.

[micasa]

Some thought-provoking responses here.

As for keeping the triarii for last - I use the hastati to absorb the charge of celtic warriors. They can take the initial heat. Then I use my best troops to put some charge back on the now spent celtic warriors. When they're tired they crumble.

As for the Hellenes, use the hastati to tie up the phalanxes and flank with some hardcore troops. From the game (again, I'm no history buff, just a casual voyeur) the Hellenic troops appear to be better armoured generally than the celts (I'm thinking Northern Gallic Swordsmen versus Classic Hoplites) so you need troops who can put some smackdown on them relatively quickly.

I'd also like to know how the hastati withdrew in real life in orderly fashion while the principes took over in orderly fashion. In the game I get my principes to charge and engage the enemy through the hastati ranks then simply tell the hastati to move back behind the principes. I lose a few guys in the withdrawal but ultimately save lives.

Whatever the case, the overall idea of engaging with fresh troops and withdrawing tiring troops for the Romans is supported in the game in some fashion but much more difficult for the Hellenes. Damn, this is a cool game!

[Decimus Attius Arbiter]

My thoughts on the triaii are that they had a defensive purpose and the first two lines did most of the fighting and manuveuring. Also, it fit the Roman social structure where it came down to the best men to recreate the defense of Rome against the Gauls and hold the enemy until the army regrouped. Also ancient armies often placed the most experienced or important men in the front and back lines for moral support and to keep them from retreating.

[Decimus Attius Arbiter]

For RTW a backwards march button would be great like CNC3.

[CaesarAugustus]

Interesting view on why the triarii were kept back pezhetairoi, it had not occured to me to think of it from a psycological/morale standpoint. But that doesn't stop me from keeping my frontline-flanking triarii units,

[pezhetairoi]

Oh, no one's stopping you from that. I use them like that all the time too. ;-) In history, *tremulous sigh* armies were not quite so easily outflanked, and most certainly not by half the army at one go... I mean, we're talking Zama and Telamon, not Chancellorsville...

[Rodion Romanovich]

Yeah, I could see the sense in the Roman formation against the Greek, because the Romans only fought on segments of the line but the Greeks couldn't exploit the gaps in between since they were largely phalangites and to do so would have broken their formation. But the barbarians... Surely they did not always charge in small tribal groups? If what we are looking at is a thirst for glory, loot, renown, etc, then once the first courageous groups starting running forward, wouldn't the rest also have gone forward, not wanting to be see to be hanging back?

Furthermore, as devil's advocate, let me offer a weakness to the short bouts of warfare point: Granted that such was the style of warfare in those days, it does not seem that the enemy would have stood by while the Roman brought up fresh troops. Their chiefs would have been able to see that for what it meant, and would have done his best to disrupt the passage of lines by possibly charging, even if his soldiers were out of juice, in an effort to catch the hastati and principes while they were still passing through, and induce confusion.

I realise there probably isn't an answer to this, but let's see how creative we can get with the answers :) Since the experts don't know either, the truth is fair game for us people. Let's postulate.

I can see a good way of using the checkerboard vs barbs: if the barbs swarm into the holes, push the principes forward a bit and compress the barbarians (against the men behind them), so they can't get enough room to swing their swords. If the barbs didn't swarm the holes, just switch between hastati and principes pushing forward/falling back in good order. The risk is of course that the entire line will be fighting at the same time at some points, and that the barbs will skirmish: threatening to enter the gap, then falling back, repeatedly, to tire the principes who would go backwards and forwards a lot (with heavier armor than the barbs wear).

But perhaps it's possible to counter this as well, by alternating between pushing the principes forward, then pushing them beyond the hastati, and the enemies in the gap would be compressed by a following (short) hastati advance. Or the principes/hastati formations could be deep enough to be able to present a deep enough front while still having men behind them move sideways into the gaps and hit the enemy flank harder than the enemy can hit the roman flanks.

In any case, by default the checkerboard doesn't give you any greater outflanking penalty than the opponent because where you are flanked, he is also flanked. Only if one side has equipment or training better suited to this kind of situation, would there be any difference. My guess is that the romans (and the samnites which they copied the checkerboard from) had made sure their equipment and training made them superior at this kind of fighting.

Anyway, I've had some fun experimenting with schemes of this type in EB

[The Internet]

I can see a good way of using the checkerboard vs barbs: if the barbs swarm into the holes, push the principes forward a bit and compress the barbarians (against the men behind them), so they can't get enough room to swing their swords. If the barbs didn't swarm the holes, just switch between hastati and principes pushing forward/falling back in good order. The risk is of course that the entire line will be fighting at the same time at some points, and that the barbs will skirmish: threatening to enter the gap, then falling back, repeatedly, to tire the principes who would go backwards and forwards a lot (with heavier armor than the barbs wear).

But perhaps it's possible to counter this as well, by alternating between pushing the principes forward, then pushing them beyond the hastati, and the enemies in the gap would be compressed by a following (short) hastati advance. Or the principes/hastati formations could be deep enough to be able to present a deep enough front while still having men behind them move sideways into the gaps and hit the enemy flank harder than the enemy can hit the roman flanks.

In any case, by default the checkerboard doesn't give you any greater outflanking penalty than the opponent because where you are flanked, he is also flanked. Only if one side has equipment or training better suited to this kind of situation, would there be any difference. My guess is that the romans (and the samnites which they copied the checkerboard from) had made sure their equipment and training made them superior at this kind of fighting.

Anyway, I've had some fun experimenting with schemes of this type in EB

As far as i know this is how it generally worked, the hastati would charge in and then the principes would charge in a short time later if needed, giving the hastati a rest. That would allow them to regroup and charge into the fray once again and then the process would be repeated, it is a very clever system and i can see why they beat much large opponents constantly through their time.

[Cash Staks]

How did the Romans actually replace the hastati with the principes? Wouldn't the gaps left between the maniples actually mean the barbarian enemy could just swarm into the gaps and outflank every maniple instantly and hit them from three sides if not all four at once, if the principes were not immediately behind the hastati? Did the hastati open up into a full line to fight before closing up into a block to withdraw through the gaps in the principes' line? And that raises the question of their vulnerability when opening and closing. Any input? It's a question that has been plaguing me to no end.

I've read a few books about how the Roman army would fight in battle and the latest one that I would reccomend is Greece and Rome at War by Peter Connely. It gives details about fighting styles from ancient Greece to Imperial Rome.

In any case, this authors believes that the army would draw up at battle in the checkerboard formation. When going to engage, the Hastati would close up, essentially that back half of each "square" would march left and then forward, thus presenting a solid line. Retreat was the opposite.

Now you pose the problem that retreating in the midst of battle would leave the Hastati open to all kinds of flanking and essentially create enormous holes in the formation. It seems that some historians believe battles were not a constant clashing of sword and shield, since this would tire out the men. Keep in mind they have armour, swords and shields to deal with. So a proposed theory is that there were breaks between clashes. This would give the Hastati time to retreat through the Principes and then the Principes could perform a similar manuever to close their line.

This is my understanding of how the Romans fought. It could be completely wrong however, and there is probably someone on the forums much more informed than I am about Roman battle tactics

[Watchman]

IMHO the mere sight of the fresh and heavily armed second-echelon maniples waiting beyond the spaces between the first-echelon maniples should have been quite enough of a deterrent to most. After all, if they tried to enter those openings they'd have the men at the flanks of the still-cohesive first-line blocks at their sides and a fresh rain of pila followed by nasty men with swords coming from the front, hardly an inviting prospect. Those gaps may well have been deathtraps waiting to close on anyone impetuous enough to enter them.

The Triarii with their heavy armour, imposing helmets and long spears would hardly have seemed any more of a welcoming prospect.

Presumably the swap between echelons was done during the inevitable "breathers" that heavy infantry cannot but have taken often enough during those long hours head-on infantry fights could take. Ditto for any "countermarching" of tired and wounded men to the rear and fresh guys into the front inside the maniples themselves. This sort of drill should have been easy enough to teach even the Republic levies - after all, other armies have made regular use of a whole lot more complicated formation evolutions with soldiers of rather lower calibre than the Roman reservists. Something like marching back and forth in synch is simple and fast enough to get into the heads of even the rawest recruits, and indeed was long something military training more or less started out with.

Although as it is difficult to see how all of the first-echelon maniples could have been unengaged simultaneousy (since it seems rather unlikely the entire enemy front line would retire to catch their breath and redress ranks all at once), the swap was presumably done on maniple-by-maniple basis as the local tactical circumstances allowed - and no doubt the entry of the fresh second-echelons rather helped persuade engaged enemies in the vicinity they had better take a step back and reassess the situation, thereby freeing the worn first-echelons to fall back.

I understand the Triarii were supposed to close the gaps between their maniples and thus form a solid unbroken phalanx in the old hoplite fashion when it became their turn though. As in principle their turn to engage came only if and when both the Hastati and Princeps had been spent and were retired to the rear, this would presumably have been a necessary move to allow the presumably by that point rather ragged maniples reform properly behind the Triarii shieldwall.

Of course, since the whole thing relied on unit drill and coordination it is easy to see why freshly raised Roman armies thrust into battle might do poorly - the men simply had not had enough time to integrate properly into cohesive units, making the maneuvering awkward. The "division of arms" was on pure financial grounds, and any given maniple would have soldiers from all over the Roman territories with greenhorns and veterans of previous campaigns all mixed together; obviously it would take a while before these mismashes learned to work together smoothly.

[pezhetairoi]

I can see a good way of using the checkerboard vs barbs: if the barbs swarm into the holes, push the principes forward a bit and compress the barbarians (against the men behind them), so they can't get enough room to swing their swords. If the barbs didn't swarm the holes, just switch between hastati and principes pushing forward/falling back in good order. The risk is of course that the entire line will be fighting at the same time at some points, and that the barbs will skirmish: threatening to enter the gap, then falling back, repeatedly, to tire the principes who would go backwards and forwards a lot (with heavier armor than the barbs wear).

But perhaps it's possible to counter this as well, by alternating between pushing the principes forward, then pushing them beyond the hastati, and the enemies in the gap would be compressed by a following (short) hastati advance. Or the principes/hastati formations could be deep enough to be able to present a deep enough front while still having men behind them move sideways into the gaps and hit the enemy flank harder than the enemy can hit the roman flanks.

In any case, by default the checkerboard doesn't give you any greater outflanking penalty than the opponent because where you are flanked, he is also flanked. Only if one side has equipment or training better suited to this kind of situation, would there be any difference. My guess is that the romans (and the samnites which they copied the checkerboard from) had made sure their equipment and training made them superior at this kind of fighting.

Anyway, I've had some fun experimenting with schemes of this type in EB

Good point there, Legio. I never thought about pushing the principes -forward- past the hastati. Hey, this could be an interesting perspective: See this. The principes and hastati push forward alternately as an offensive technique. The hastati engage, then if the principes come up and the enemy pause in confusion, then the principes take the initiative and take the offensive. And once the principes bog down, the now-rested or at least less-tired hastati move forward again and if the enemy pause, they take the offensive past the principes, who do not move back through the lines, but stay where they are to be the next second line, with the effect that the entire triplex acies moves forwards instead of backwards. The same attritional effect would apply.

Though of course this only occurs in situations where the opening presents itself, obviously, since sometimes the enemy is too strong for you to take other than the defensive. But we can see some potential of this applied to, say, Kynoskephalai and Pydna, where maniples -from the second line- would go to the attack into gaps in the phalanx when they went over uneven ground while the maniples in the first line would continue keeping them occupied.

Thoughts?

[Watchman]

That seems to rely a bit too heavily on actually being able to push back the enemy battleline, which is AFAIK by far easier said than done. I've always gotten the impression the Roman tactical system was designed more for victory through sheer attrition, that is, wearing the enemy out with successive attack waves while preserving the integrity and cohesion of their own units through the rotation system.

[pezhetairoi]

Well, they wouldn't really be pushing -back- the enemy line, I was looking more at them pushing -into- the enemy line. In rigid formations like the phalanx they would literally be penetrating into the ranks, while against loose-order formations like the Celtic armies they would just advance instead of waiting for the enemy to charge so as to disrupt their charge, and perhaps force them in essence to retreat further backwards every time they drew a breath since each time they did so the second line would leapfrog forward to close the distance or launch a new attack. It would be attritional still, and it would have the benefit of giving the enemy no time to catch his breath before he has to deal with a new attack. Instead of dealing with the enemy's waves of attack, now it's the Romani who deal a sustained attack on the offensive.