How accurately could ancient soldiers/commanders maneuver during battles

Question

I am currently working on a small strategy game/interactive simulation of historical battles, whose main goal is to give the player – playing as the general of a ancient army – a more realistic amount of control of the soldiers of the said army and more realistically depict the amount of information available to a commander in this time.

One important feature will, of course, be that the player won't be able to maneuver their soldiers around -- especially during battles -- in a way, in which a historical commander in ancient time (by which I primarrily mean circa 400 BCE to about the fall of Rome and primarily in a European/mediteranian context) would not have been able to communicate with his soldiers, making use of, for instance, flag-, trumpet or lantern signals or messengers running to and from the different parts of the army, and also in which the soldiers in a medieval or ancient army would be able to accurately understand or interpret.

I do acknowledge that great differences may exist in this regard between, for instance, the legions of the Romans and the Gauls, but I do still assume (correct me if I am wrong) that the lack of radio -- throughout both antiquity and the medieval period -- still makes it possible to say something about this which in general applies to both ancient and medieval armies.
If the differences between these groups, in this regard, are significant, I would like to know in what way they differ.

Specifically, I am interested in the following:

• Is it at all accurate to divide the army into units of specific sizes, which acts may be thought of as one (making any games much easier to make), or would the entire front line melt together to one large mob of people? (and where units such as the Roman cohort thus merely a logistical tool rather than a combat unit).

• During a battle and lacking any significant landscape features, How accurately (if at all) would a commander in ancient time be able to tell a group of their soldiers to move a specific distance or turn a specific angle?

• During a battle, lacking any significant landscape features, how accurately would these soldiers have the ability to judge said angle or said distance?

• would am ancient commander during battle be able to tell a group of his soldiers to attack (or aim for) a specific part of the enemy army? (for instance, tell their archers to aim for the place where someone spotted the enemy commander)

• would am ancient commander be able to tell a group of his soldiers to move to notable landscape features (trees, houses, hills etc., and how notable would these features have to be)

• How accurately would an ancient commander be able to tell a group of his soldiers to move around relative to their own army (for instance, move units from one flank to the other to prevent encirclement)

I would also very much appreciate references to either historical sources or reliable modern reenactments/experiments.

Answer 1

Is it at all accurate to divide the army into units of specific sizes.

Of course, you're making a game. You have to make a balance between playability and reality. A Roman cohort has 480 officers and men as optimal strength, with the first cohort being a double cohort of 960 men. In a game you don't want that kind of precision.

In real life no cohort had that number, ever. None of cohorts II-X even had the same number of legionaries. It's purely theoretical. You can, for the sake of playability, set the number to any theoretical value you like.

During a battle and lacking any significant landscape features, How accurately (if at all) would a commander in ancient time be able to tell a group of their soldiers to move a specific distance or turn a specific angle?

That varies with the landscape and the weather. If the commander is lucky enough to stand on a hill top on a sunny day, quite a distance. If on flat ground on a foggy day, not a damned thing. ;-)

During a battle, lacking any significant landscape features, how accurately would these soldiers have the ability to judge said angle or said distance?

Soldiers are trained to use their weapons proficiently. A legionary would be in deep shit if he couldn't throw his pilum accurately 15-30 meters. That includes judging that distance accurately, and throwing 1-2 pilums accurately and in rapid succession as a unit before using his gladius. Standards were much higher for professionals than for unwilling conscripts, of course.

In your game professionals should act as professionals. But a bunch of drafted very unwilling farmers can easily stand dumbfounded watching the officer shouting the top of his head off to get his men to do what he wants. It did happen. (And can be quite amusing to see in a game.)

would am ancient commander during battle be able to tell a group of his soldiers to attack (or aim for) a specific part of the enemy army? (for instance, tell their archers to aim for the place where someone spotted the enemy commander)

That depends a lot on the clothing his troops wore. One of the many reasons why soldiers didn't wear camouflage is a) it didn't work on those short distances b) it makes a soldier more impressive and proud and c) so the commanders could see who and where they were. In ancient times nobody wore an uniform. Not even the Romans did. The concept as we know it hadn't been invented as yet.

would am ancient commander be able to tell a group of his soldiers to move to notable landscape features (trees, houses, hills etc., and how notable would these features have to be)

Yes he could, but that would be micro management and that's generally a very bad thing. The general would command his officer to do this or that. The officer would himself decide to use that landcape feature or not.

How accurately would an ancient commander be able to tell a group of his soldiers to move around relative to their own army (for instance, move units from one flank to the other to prevent encirclement)

Not very. Communications are limited during combat. In theory he could send a runner, order signals by trumpet or visual with banners and flags. In real life those runners could be killed before delivering the message. The troops didn't hear the signal due to the noise on the battlefield (happened to Caesar during the siege of Gergovia), or didn't understand what exactly to do, and did the wrong thing (charge of the light brigade). In that case, the runner himself completely misunderstood the message he was supposed to deliver and gave his own interpretation of it.

As for banners and flags: they were used, of course. But much more before the battle began, because soldiers during a battle tend to focus on staying alive. Not what the flag is doing.

Hope it helps you a bit.

Answer 2

I have taken part in, and commanded LARP-battles (stop laughing! :-), with swords, shields, lances and archers, and can relate that for an observer, any meter of elevation is a real revelation. Commanding is so slow, and non-realtime, though, so all that insight is mostly for posterity. Troops need to be instructed beforehand, and given if-then types of orders relating to landmarks, enemy troops, times, and horn-signals ('crush archers, but do not advance beyond that treeline, retreat on hearing five blows, ...').

Landmarks always were a major factor. Hills, treelines, brooks - they all give a point of reference while also being tactical faultlines.

Scouts are invaluable, even their absence ('all scouts going south did not return') is information. But their info gets more outdated the farther they roam. Velocity of Information distribution is a major factor.

If you want to go for realism, do not show the battlefield, but show the battlefield as the commander imagines it. 'Nobody told me there was a cliff there!' plop cliff ---- 'what do you mean Carl and his troops are late? They should have been hacking at the flanks for the last hour! Where are they?' Re-strengthen enemy flanks, remove Carl's troops --- 'i've had no reports from our troops waiting in that grove all morning -send a runner to investigate!' grey out troops in grove

Answer 3

Potentially interesting source: https://en.wikipedia.org/wiki/Military_strategy

As this seems to be for a game I'll stick to some (hopefully educated) guesses.

Is it at all accurate to divide the army into units of specific sizes, which acts may be thought of as one (making any games much easier to make), or would the entire front line melt together to one large mob of people? (and where units such as the Roman cohort thus merely a logistical tool rather than a combat unit).

Neither or both insofar as I'm aware. More or less like today, you'd divide your army into units, each with subunits and sub-subunits etc., and basically have each level assign a goal to the level beneath it, with a caveat.

One difference in medieval times and earlier is that the units weren't really considered autonomous. Giving high autonomy to units came during WW2 if memory serves me well (it was a Nazi/Blitzkrieg innovation). So you can kind of think of earlier units as basically not knowing what to do unless a courier or some horn signal reaches them or the pre-agreed battle plan made what to do explicit, with some variance for stubborn/brave/silly leaders.

During a battle and lacking any significant landscape features, How accurately (if at all) would a commander in ancient time be able to tell a group of their soldiers to move a specific distance or turn a specific angle?

As you pointed out they relied on horns (and couriers), so not very.

During a battle, lacking any significant landscape features, how accurately would these soldiers have the ability to judge said angle or said distance?

Inaccurate. You'd likely aim at some landmark.

would am ancient commander during battle be able to tell a group of his soldiers to attack (or aim for) a specific part of the enemy army? (for instance, tell their archers to aim for the place where someone spotted the enemy commander)

Likely, with the caveat that like today taking out the main commander just means someone else takes over as commander and it's likely the troops wouldn't notice the difference.

would am ancient commander be able to tell a group of his soldiers to move to notable landscape features (trees, houses, hills etc., and how notable would these features have to be)

Be wary of a possible premise here: namely the assumption that the commander has some godlike ability to see the battlefield from above. They did not. If there's a feature behind the hill ahead of you, you simply wouldn't be aware about it unless you've sent scouts who told you they're there.

Assuming the commander is aware of the feature, then yes of course.

How accurately would an ancient commander be able to tell a group of his soldiers to move around relative to their own army (for instance, move units from one flank to the other to prevent encirclement)

Hopefully one of our Roman history experts will chime in with sources rather than guesswork, but that I'd surmise likely. In ancient times battles were very much about encircling your opponent and avoiding to get encircled yourself, with cavalry thrown in to flank lines, wreck them in case of contact, and slaughter them in case they retreated. Getting flanked by infantry likely was a good reason to pivot and build a shield wall; getting flanked by a roaring cavalry charge was a good reason to not stay around to be on its receiving end.