How would Roman legions fare against Medieval armies?

[Death Merchant]

First off I think the Roman army of the 1st and 2nd century was most powerful it had both powerful infantry and resonably strong cavalry such as sarmatian and german cavalry which were recruted outisde the empire eqiupped with roman weponry and tactics these could match any "barbarian cavalry"

This would most probably slaughter a medieval army in the year 1000 armies consisted of levies usually with crude swords and spears and usually a couple hundred elite knights and sometimes some proffesional troops

But later in medieval times like the Early 16th century i think the tables would turn the spanish "tercio square" was a tactic that ended the era of heavily armoured knights and chivalry this consisted of proffesional tercio pikemen which would protect the aquebusiers and musketeers plus the cannons behind them the pike was extremely difficult to brake at least as powerful as any greek phalanx if the pikes could not be broken then the gunners would shoot all day long and blow the living hell out of the enemy until the enemy retreted or nightfall

I dont think the Romans would be able to counter such a tactic sure they broke the macedonian phlalanx at cynoscephalae in 197bc but classical phalanxes were agian lagely levies with little armour Tercios were well armed and eqiuped proffesionals Historians have also argued that the macedonians only lost because of the rough terrain in which they were deployed made a unbroken phalanx difficult to accomplish and the presence of roman elephants which terrified the macedonians

[Kalis]

Eric:
if you want a more in-depth explanation, it all goes back to tactical flexibility, and how the units are used. Yes it's really RTS-ish, but... it applies
(And sorry if I'm going into information overload hehe - military history is one of my favourite subjects and I read voraciously about it).

The first step to it is discipline, and whether the commander can actually use the units against what he wants. This is something that is completely missing from Medieval armies. There were no "instant orders and responses" the way we get from strategy games (or modern warfare though radios). This is why things like ECM and ECCM are so important in modern warfare. If you disrupt the chain of command, you can isolate and kill. But I digress. Let's just assume both sides have perfect discipline, and the generals have the ability to give troops commands (so cavalry will always hit light infantry and such, and so forth). In other words, we're talking "set piece battles" only.

The second step is the army composition. You absolutely cannot have a purely heavy infantry force because the heavy infantry will never be able to catch or touch light infantry for example. That's where your example comes in. The light infantry (slingers) were able to harass the greek phalanx who couldn't catch them, and had no cavalry to catch them either.
Thus, all ideal armies are mixed forces: some light infantry, some heavy, some cavalry (light or heavy).

The greatness of the roman legions was it's combat power and the fact that there were only 4-5 major defeats in their entire history. They loss more battles than that, but in those battles, the army was not shattered, so they would retreat and regroup and be ready to fight another day, when they could win. All the major defeats came when the heavy infantry became isolated without support, so they couldn't extract themselves.

Taking Adrianople as an example.
The roman army was primarily heavy infantry, but it also had light cavalry (melee only) and skirmishers supporting it.
The Visigoth army was infantry (in a defensive circle with wagons protecting them) with heavy cavalry.

What happened there was that visigoth heavy cavalry routed roman light cavalry. At this point, it became heavy cavalry + infantry vs heavy infantry only. They couldn't retreat in good order (because the Visigoths charged the roman lines again and again), so when the rout started, they were slaughtered by the thousands.

Carrhae, same thing happened. Constant harassment by cavalry archers let the heavy cavalry charge in again and again. In that battle, the Parthians didn't even bring infantry! Just 10,000 cavalry vs 40,000-45,000 romans, and they won with minimal casualties!

Cannae was a tactical masterpiece by Hannibal where he positioned his inferior army so perfectly that his weaker cavalry routed the roman cavalry, and then slammed into the roman infantry from behind while his infantry fought them. Hammer and anvil. It's the simple RTS theory, which actually managed to be applied (and it almost never is). In fact, it's a battle of such tactical genius that it is studied in depth by modern militaries. That said, despite his tactical genius, Hannibal was ultimately a bad strategist. The victory at Cannae had left the Roman empire open. He could of marched upon and razed Rome, but he didn't do anything. And so eventually, Rome was able to form a new army, under a brilliant general - Scipio Africanus, who defeated him.

So basically, to conquer the world, you need a balanced force and the ability to minimize casualties, even in battles you lose. The greek city states never conquered the world because the hoplite was only 1 individual force. They did completely beat the crap out of the persians though (who were purely lightly armoured swordsmen and light cavalry which can do nothing to hoplites).

But Alexander did. He added the companion cavalry to the hoplites. Suddenly, there was a force capable on conquering the world. His phalanx would form a battleline (anvil), and his cavalry was the hammer he used to crush the enemies (and deal with ranged light infantry). Admittedly, part of it is that no army he faced every had disciplined spearmen (who would be able to crush his cavalry anvil).

The Romans did. Their infantry force slaughtered the swordsmen infantry forces they faced, and light cavalry support dealt with the light infantry (archers, slingers) which the legionaires could not catch. The conquered everything until they met heavy cavalry, which their legionaires were inherently vulnerable to. They could never conquer the east because of it (where they had cataphracts).

Finally, the Mongols did. They did it with light cavalry archers, which truly have no weakness. Attack from afar and never get into the melee. Melee only to break the spirit of the enemy, or when you outnumber them and can attack from all sides (all the little ambushes they form to kill the European knights). No historian doubts the Mongols could of easily conquered Europe. They conquered China. They conquered Persia, an empire the Romans were never able to defeat. They conquered Russia in a winter campaign, the only army in history who ever did that (Both Napolean and Nazi Germany tried the same and failed because of the brutal Russian winters). The only reason they stopped conquering was because Genghis Khan died, and they went home to elect a new leader. But within 100 years, they formed the largest continental empire the world had ever seen, and the second largest empire overall. The largest was the British Empire (and that is only because they held Canada - which is incredibly large but also completely unpopulated lol). Compare this to the Roman Empire, which began as the republic at 517BC and only reached its zenith at around 100AD, or 600 years of battle and conquest.

edit:
that said, conquest is not the same as actually holding what you take
Just because you can conquer doesn't mean you're good administrators and won't get rebellions.
For example, despite being the first to fall, China never accepted the Mongols as "real" emperors, and as soon as they were able, they threw off mongol rule

Still. there's very good reason why they succeeded:
http://www.uwgb.edu/dutchs/WestTech/xmongol.htm

Why the Mongols Succeeded

Mongol battle tactics were an outgrowth of their natural lifestyle. Between their nomadism and their traditional clan warfare, they received constant practice in riding and archery. Unlike the cumbersome European armies of the time, the Mongols traveled very light and demonstrated extraordinary endurance, living off the land and often spending several days at a time in the saddle.

Once they launched their conquests, they demonstrated remarkable ability to coordinate armies separated by great distances, using dispatch riders to communicate across hundreds of miles of unfamiliar terrain. Their mobility - up to 100 miles a day - was unheard of by armies of the time. The Mongol combination of mobility and communication was probably not equaled again until World War II. Time and again we read of the Mongols performing feats that would not be matched until the Twentieth Century; it's as if Erwin Rommel and George Patton fell through a crack in space-time and came out in the Thirteenth Century.

Mongol tactics were innovative. A favorite ruse was to open a hole in their lines and allow panicked enemy soldiers to flee. After wiping out the disciplined troops who remained, the Mongols hunted down the stragglers. A similar ruse was to put up a stiff fight, then retreat and lead pursuers into an ambush. The Mongols were extremely ruthless in battle but displayed extraordinary military discipline. When a Mongol general violated orders and sacked a city promised to another chief, Genghis Khan ordered him to step down and serve as a common soldier in his own army, which he did, falling soon afterward in battle. Almost alone of the world's armies of the time, the Mongols could be ordered not to pillage a city and would obey; contrast the Crusader sack of Jerusalem in 1099. Although originally nomads, the Mongols were very pragmatic about adopting useful innovations and readily assimilated advanced siege technology. And they were superb and voracious gatherers and users of military intelligence.
Mongol rule in conquered territories had two faces. Resistance and rebellion was countered by ruthless annihilation, but Mongol rule was remarkably benevolent when the populace was cooperative. Conquered areas were generally left under native governors (China was the exception; there the Mongols tended to use outsiders whenever possible). Religious tolerance was important in consolidating rule and gaining the support of minorities oppressed by Moslems. The administration was commonly more benign than pre-Mongol government. In the conquest of Persia, these strategies amounted to "Resist, and you die; cooperate, and you will be better off." This attitude wasn't entirely restricted to the Mongols; the prevailing rule of war was that a besieged city could obtain surrender terms, but if the city resisted and forced the issue to the bitter end, it would bear the consequences.

[Eric]

Horse archers have their weaknesses. Since there primary weapons are bow and arrow, you send close-combat light cavalry against them, cavalry capable of chasing them down, closing fast, and engaging them hand-to-hand where they can't use their range advantage, and they will be slaughtered. They are also incapable of holding a defensive position. I'd like to see a horse-archer army hold a castle, or a fortified city. They can't, to man the walls they must dismount, which takes away their mobility advantage, also, in the narrow streets they cannot use typical horse archer tactics (come in close, fire arrows, retreat, repeat) with any efficieny. Horsemen of the sort the Mongols used to great efficiency require wide open spaces for their tactics, they can't fight in mountains, or foothills. Another disadvantage. Horse archers are at a disadvantage for siege. In order to scale walls, you must be on foot, you must bring along siege to bring down the walls, which slows the horsemen down, and makes them vulnerable. If they get too far ahead of their siege train, their siege train and supply line will be cut off, and they'll be unable to take the fortress. No Mongols could not of conquered Europe. Castle, after castle, after heavily fortified castle would of prevented that. The hundreds upon hundreds of fortified positions the Europeans had would of prevented the Mongols from conquering. Sure, they could overrun the land, but they would never be able to conquer the castles with their form of warfare, which emphasized speed and shock. They would become bogged down in a battle of attrition with the European castle-dwellers which they could not win. A battle of attrition that the Mongols would have to fight to take a castle would remove their speed and they would be doomed, basically. Eventually they would be forced to withdraw, exhausting their supplies and men from throwing them in waves against the rocks that were Medieval castles.

[Kalis]

Eric:
You're going too much into RTS there Specifically, real life soldiers don't play 1 role and 1 role only. For example, knights often dismount and fit as heavy infantry. Similarly, England's longbowmen could function as light infantry as well. In fact, Agincourt was a batlte where the English knights were dismounted, and the longbows killed the french knights with the mallets they carry to drive stakes into the ground.

Similarly, mongol horse archers that also carried spears. So they were horse archers that are also light cavalry. This basically means no cavalry was capable of catching the mongol horses. Light cavalry moves at the same speed as horse archers, so you'll never catch them unless they want you to. Which is part of mongol tactics. Feint retreat, make the enemy cavalry follow you into a trap, and then pepper them to death with arrows. Also, horse archers are basically archers. If you dismount mongol troops, they're foot archers, who can easily defend a castle or fortified city. Or light spearmen if you wish.

Finally, China had lots of castles. They conquered it.
The Persian empire was filled with fortified cities. They conquered it.
Russia was castles. They conquered it.
In fact, it was the mongols who brought gunpowder to Europe. They learned siegecraft from their conquest of China, and they hired a lot of expert engineers to support their armies when they attacked Persia and beyond.

And again from the above link:

Bela (The ruler of Hungary in 1241) prepared as well as any European ruler could, but he was no match for the Mongols. He blocked the mountain passes in the Carpathians with his best troops and hurried back to Buda (In those days Budapest was two cities, Buda west of the Danube and Pest to the east) to convene parliament. He was hardly there when a messenger arrived with the news that the mountain passes had been overrun; three days later Mongol raiders were outside Buda, having covered 300 miles through hostile territory in three days. In a few months the Mongols had smashed all military opposition in Poland and the Balkans and were regrouping to push west. Given this pace and their performance in Persia, they could probably have overrun Europe in a year. But just as they were regrouping, a messenger came with the news of the death of the Khan. Genghis Khan had made a law, to ensure the permanence of his dynasty, that all his descendants, wherever they may be, must return to Karakoram to elect a new Khan. The Mongols broke off the invasion, never to return. This is surely one of the most important but least-known turning points in history.

Incidentally,
Poland, Hungary and Russia were all premier European nations at that time, with lots of castles and large (by European standards) armies.
Of course when you're fielding armies of 5000 soldiers tops, while the Mongols have running around with 3-4 armies of 20000-30000 horse archers (who could also split into small armies if necessary)...
Castles weren't a thing only western European nations used. The Persians and the Chinese had them too.

And it also addresses the other point:

In What If?, a collection of essays on alternative military history, Cecilia Holland pictures the likely result of a Mongol thrust into Western Europe. She pictures a massive raid rather than a complete occupation; nevertheless, the picture she paints is chilling. Driving across the North German plain, the same route Cold War planners pictured for a Soviet invasion, the Mongols would have made use of expert reconnaissance to target plunder and grazing land. They would have sacked Belgium and Holland, destroying the embryonic financial centers of Europe. They would have turned south into France, destroying Paris and with it the revival of ancient philosophy that it would have hosted a few decades later. Perhaps they would have crossed the Alps and ravaged Italy, destroying the other birthplaces of the Renaissance. In his foreword to the piece, editor Robert Cowley says "The Dark Ages were pure light compared to what could have happened..."

Sure you have castles, but if they were settling on raiding and pillaging instead of conquest, it's easy to go around the castles and loot population centers. European armies at that time were trying to conquer, not destroy. Big difference if all you're after is destruction (or to drive the enemy to surrender through economic destruction).

Think... WW2 Germany attacking France. France had this nice large trench warfare line, and Germany just went around it through Belgium and the Netherlands and gutted the French territory, making them surrender.

[Eric]

Exactly. You claim the Mongols could conquer Europe, then turn right around and say they could settle for loot and pillage. And loot and pillage is ultimately what the Mongols wanted. The only Empire-builder of the lot of them was Genghis himself. And he was of an exceptional breed. Great tactician, great strategist, great ruler and administrator. The rest of them were happy just to loot, and pillage, like the Huns before them. Castles, by the 13th century, the time in which the Mongols were invading, were all but self-sufficient. They were built on high rocky ground, often near water which they channeled in a moat. There, they have a limitless water supply. Within there would be gardens and small livestock enclosures, food. The concentric castle of 13th century Europe is one of the most imposing fortifications ever. Causways, layer after layer of tall, thick wall. Sure the Mongols with their mounted archers could ride around the castle, burn the fields, loot the towns. The Europeans would sit tight in their stronghold and when the Mongols moved on, they'd come back out and rebuild their towns and continue on with life, and when the Mongols came back, they'd just go back into their fortress and so it would repeat. Horse archers are formidable, no doubt, but just like the airforce today, you will always need a man on the ground, a soldier on his own two feet, to take and hold ground.

[Bonifacius]

I always read that the Mongols brought chinese engineers with them and as a result were masters at siege warfare. Then again, I also read that many cities simply opened their gates to the mongols out of fear of a total massacre. Wait! But I also read that Ghengis's mongols were given credit for the deeds of tamerlane 200 years after the mongol invasions..... Which one is it?

[Odovacar]

Kalis: I like the way you are arguing. You use arguments, instead of merely worshipping romans. However, I think you are very mistaken in some of your posts.

Took at the two battles I laid before you as examples:
In Benevento Manfred's german knights were not reinforced in time. Manfred himself commanded to charge them, no one else.

In Tagliacozzo, Conradin's knights exhibited very foolish behaviour. Oops, an argument on your side! But! The enemy could only turn this to his own advantage, because Charles was hiding on the battlefield, and one of his experienced commanders (a crusader) holped him with advice, like luring away troops in fake retreats. And Charles had knights as well.

The french marshal D'Albert was maybe a good soldier, but the french generals of hundred years war were not tactical geniuses. I wonder if he even tried to withold the knight's charge.

A further example: at the battle of Mahrenfeld, in 1266, King Otokars knights were attacked by cumans as the hungarian army was marching on the bridge. In countercharge, the knights drove back the cumans who then turned back the whole army, causing them panick. It was the cuman warrior, not the knight here who acted without discipline.

At the battle of Dürnkrut Rudolf von Habsburg has hidden a group of knights in the nearby forrests, and that group attacked Otakar from behind, thus winning the battle. You give the example of english knights as an exception, and the example of french knights as a law, however, the background caused the difference. German, hungarian warriors rarely fought like french did.

Berthold of Emmerberg for example warned an austrian army when it was about to attack a hungarian one, not to hope an open fight, but prepare for skirmish.

Eric:
Similarly, mongol horse archers that also carried spears.

No, how could a horse archer carry a spear? They carried a pickaxe.
They had heavy cavalry to support them.

They learned siegecraft from their conquest of China, and they hired a lot of expert engineers to support their armies when they attacked Persia and beyond.

The mongols took cities with lots of hungering and panicked people. The art of building castles (like the Chateu Galliard) according to western standards was not known in the east, it was based on western feudal system. The mongols learnt nothing, they used the knowledge their captives.
The mongol army in the 1241 took no castles as far as I know.
And not much cities either. Although they have months to do so.
By that time they possessed not much chinese engineers.

Incidentally,
Poland, Hungary and Russia were all premier European nations at that time, with lots of castles and large (by European standards) armies.
Of course when you're fielding armies of 5000 soldiers tops, while the Mongols have running around with 3-4 armies of 20000-30000 horse archers (who could also split into small armies if necessary)...
Castles weren't a thing only western European nations used. The Persians and the Chinese had them too.

Premier nations?
In Germany or Francr there were far greater castles, and far more stone castles, and the kings and lords had greater income.
Please see my thread about the Battle of Muhi. You will see how the popular misconceptions about medieval/eastern european warfare, castles are silly.
Russia was a heavily divided country with lots of quarreling princes, and without proper castles. Poland similar. In Hungary the nobles wished to see the king defeated. Most hungarian castles (there was around 70-100 of them) were wooden fortifications. The few stone castles however withstand the mongol attacks. Hungary could not even muster many knights, the modern armour was a rarity in Hungary.
And 'medieval levies' were nobleman who could posess good weapons, made in Germany or in the east.
Also, beating someone with superior numbers doesn't prove that you are a genius level general, or a superior soldier.

[Hellenic Hoplite]

'The Romans' and 'the medievals'. How very simplistic generalization. Not all Romans were disciplined, and I really doubt that as a whole they were any more disciplined than a professional medieval army. To me that's an insubstantial question that cannot really be answered.

[Freddie]

(Says a lot of things)

I always thought the Goth cavalry was nomadic, smaller, faster cavalry. Maybe someone can clear this up.

However I don't buy the fact that the battle of Adrianople was won by the use of heavy cavalry which was to strong for Roman heavy infantry. All it proved was if you out flank infantry with cavalry your cavalry will be successful in routing infantry, which is no different then any other battle in history, whether it be light cavalry or heavy cavalry.

And to tar medieval infantry with the same brush as ancient Britons and Gaul’s is wrong. Medieval infantry were not warriors, but the vast bulk (and I’m not talking about Knights) were paid mercenaries, or trained commoners. There are book in the British War musem which were written by German showig how armies used to train with weapons, they even had training for when you got disamred, it's amazing stuff.

[Flavius Nevitta]

[CENTER][FONT="Comic Sans MS"][COLOR="Green"]I always thought the Goth cavalry was nomadic, smaller, faster cavalry. Maybe someone can clear this up.

However I don't buy the fact that the battle of Adrianople was won by the use of heavy cavalry which was to strong for Roman heavy infantry. All it proved was if you out flank infantry with cavalry your cavalry will be successful in routing infantry, which is no different then any other battle in history, whether it be light cavalry or heavy cavalry.

You are correct. This battle can not be taken as an example of heavy cav beating infantry. Actually heavy infantry, if kept in close formation, is superior to heavy cavalry during all periods. The problem for the Romans at Adrianopolis was that their army was not properly deployed to use its numbers and strenght. The infantry was ordered to charge the camp. Valens thought he could take it with a single all out charge. He greately underestimated the goths and their fortifications. The infantry tried to push through the "gates" which caused confusion and a complete mess within the Roman troops while the goths within the camp could concentrate on fighting the few Romans who pushed through the open parts of the fortifications at a time. So while the Roman infantry lost formation and turned into a huge, confused mass of people trying to push forward the goths were able to use their troops as effectively as possible.

The Romans had numerical advantage on the battlefield BUT the Goths through their fortifications and the completely confused all out charge of the Romans were able to gain numerical superiority at the "hot spots" where the actual fighting took place. What actually happened was practically the same situation as in Cannae. While the Roman infantry was too tightly packed and only a very small minority of their troops could actually fight the rest was thrown into complete confusion and unable to make any manouvers anymore. The Roman cavalry which was practically out of the game so far was surprised by the Germanic cavalry as they didn't think they were there. The cavalry fled the field because of this surprise attack on them and left the infantry alone.

Noticing what happened the infantry tried to react (those who had noticed what was going on) but was unable because units had been mixed up and because of the mass pressure.Moral broke and they tried to flee or retreat which was impossible as there was no chance to restore order and the routing troops were easily chased down by the Gothic cavalry.

[Last Roman]

The mongol army in the 1241 took no castles as far as I know.
And not much cities either. Although they have months to do so.
By that time they possessed not much chinese engineers.

I'm going to have to disagree. The Mongols had overtaken many cities by that time (mostly in China) and had learned how to use siege weapons. True, they learned it from the Chinese. But I see it as a strength, not a weakness, to learn from an enemy (The Romans did the same)

[Odovacar]

I'm going to have to disagree. The Mongols had overtaken many cities by that time (mostly in China) and had learned how to use siege weapons. True, they learned it from the Chinese. But I see it as a strength, not a weakness, to learn from an enemy (The Romans did the same)

I was referring to the mongol campaign in Hungary in 1241 where they failed to take castles. Capturing fortified cities is not the same, easier.
Learning from the enemy is really not a weakness, however the mongols did not learn much. They not adapted anything new. Once their chinese engineers died they did not start to produce mongol engineers.

[Last Roman]

I was referring to the mongol campaign in Hungary in 1241 where they failed to take castles.

oh. my bad

[Holger Danske]

'The Romans' and 'the medievals'. How very simplistic generalization. Not all Romans were disciplined, and I really doubt that as a whole they were any more disciplined than a professional medieval army. To me that's an insubstantial question that cannot really be answered.

The Roman armies were peasant armies until Marius made his reforms, and made the Roman army a standing professional military force
- professional meaning that the soldiers where trained in close combat, formations, and trained to follow orders.
Typical medieval armies from 1000-1500 were as mentioned before bands of peasants lead by a few nobles and elite mercenary troops. With some few armies standing out as exceptions. I would love to know which typical medieval army system (1000-1500) that was even close to the Roman legions of the 1st and 2nd century.

[Phaedo]

The Roman armies were peasant armies until Marius made his reforms, and made the Roman army a standing professional military force
- professional meaning that the soldiers where trained in close combat, formations, and trained to follow orders.
Typical medieval armies from 1000-1500 were as mentioned before bands of peasants lead by a few nobles and elite mercenary troops. With some few armies standing out as exceptions. I would love to know which typical medieval army system (1000-1500) that was even close to the Roman legions of the 1st and 2nd century.

You might take a glance at the Venetian armies used for campaigns in mainland Italy during the late 15th century.

Venetian native troops, although primarily militia, still had an exceptional degree of training and esprit de corps, along with remarkably uniform equipment. The militia reforms instituted by Domenico Michiel in the early 12th century ensured a large pool of able reserves that the Republic could call upon in moments of crisis (such as the task force of Venetian militia that retook S. Giorgio Maggiore during the final Genoese siege of the city). Moreover, the semi-professional Arsenalotti (which were technically the guards of the Arsenal and honorary guards of the Doge, but in reality were a state-subsidized "select corps") provided a strong backbone to Venetian infantry. The reforms of Domenico Michiel instituted mandatory crossbow practice for the militia units, and provided for their organization along neighborhood lines - much like other city-states of the time, but the units were given far less free-rein. In times of war, the native Venetian infantry would be supplemented by the retinues of mercenary captains - Gattamelatta and Bartolommeo Colleoni being prime examples.

In cavalry, the Venetians were not lacking. Both the famous stradioti and military levies of noblemen from their mainland possessions in the Veneto provided a well-balanced and disciplined force, not prone to rash charges - although to be honest the stereotypical "headlong charge" was not uniform or even really widespread amongst European armies of the time.

The battle of Agnadello during the war of the League of Cambrai is often used to condemn the Venetian military system - but the mercenary captain in command of the forces of the Republic, Bartolomeo d'Alviano did quite well against the French, repelling both cavalry and pikemen until the refusal of the Venetian mercenary company under Nicole, Count of Pitigliano to engage the flank of the French forces allowed Alviano to be overrun by the French reserves.

In organization, versatility, and leadership, I'd vouch for the land armies of Venice as somewhat comparable to that of the professional Roman army.

[Kscott]

Horse archers have their weaknesses. Since there primary weapons are bow and arrow, you send close-combat light cavalry against them, cavalry capable of chasing them down, closing fast, and engaging them hand-to-hand where they can't use their range advantage, and they will be slaughtered.

Horse Archer's aren't just archers. All horse archers would carry some secondary weapon and were very efficient with them. Unless you hold numerical superiority attacking horse archers in real life with light cavalry is a very dangerous maneuver.

The only Empire-builder of the lot of them was Genghis himself.

Please don't make large claims about things you are apparently unaware of. The height of the Mongol conquests occurred after Genghis died under Ogodei. Hulaugu, Mongke, Kublai are other notable empire builders. The lands of China were not looted, they became a new Chinese dynasty. In the middle east they created the Ilkhanate which was essentially just another manifestation of Persia. And the Golden Horde? They were the overlords of the Russians for more than a century. The MMongols did come to loot, but once looting was done they came to stay. To say otherwise is simply ignoring a large part of history.

[Rion]

proximo

Cataphracts didn't use stirrups as said earlier in this thread.


Odovacar

Wasn't Richard Neville the Kingmaker the Earl of Warwick during the Rose Wars?
Anyway, the author of this thread clearly said that the Medieval armies should be pre-gunpowder and I don't think Richard Neville, the Condottierre, English Longbows, John Hawkwood and Bill-hooks was pre-gunpowder.

[Odovacar]

Richard Neville was the Earl of Warwick, and lived in the gunpowder age. I am aware of the original poster's intentions.
However I dont know why should be Warwick different than any other medieval generals. Gunpowder was not widely in use in the War of Roses, and had no part in Warwick's success.
Even we leave him out there are plenty of examples to medieval commanders using knights effectively.

[Kalis]

Let's phrase it this way: The Roman army had lots of commanders, subcommanders, etc. You know, Decurions, , centurions, primus pilus, military tribunes, etc.
In other words, they had a very deep chain of command that they could draw on even in battle, in case communications with the general was cut off. And with their communications systems, a general could issue orders to troops at the other side of the battle.

By comparison, Medieval armies generally had the overall general, and a few experienced commanders. They didn't have much of a communications system either. As a result, both the general and the commands could pretty much only order the units close to them. They couldn't really have overall command of the battle. For example, they were in the center, and a flank of the army was breaking. Even if they saw it, they couldn't order troops to reinforce. They would have to hope someone there saw it and could give that order.

In other words, because medieval generals could not give an order to their army during a battle, a Roman army with a brilliant general had an edge over a medieval army with a brilliant general.

Also, it's just the difference in battle styles: I firmly believe the Roman battle style of tower shields + gladius would beat the Medieval battle style of longsword + kite shield.

Also, discipline and chain of command was something almost all medieval armies lacked. There might be elite units, but there was never an elite army. In terms of tactical flexibility, medieval armies had none. Certain sections might have great tactical flexiblity, but only a few sections.

Odovacar:
You're right, I'll admit, I definitely just made assumptions in some cases But while I'm mistaken in the examples and precise facts, I firmly believe that I'm correct in the overall conclusions

A few responses though:
- At Benevento, I'm pretty sure it's unknown whether he commanded the charge or not. We know it occurred, but from what I know, we have no proof that he himself ordered it.
The problem with knowing whether commanders issued orders is that unless it's clearly recorded, we don't know. And in this case, Manfred lost the battle, and history is always written by the victors.

Tagliacozzo (I'll admit, I never studied the battle. I just relied on the quick summary from wikipedia):
- Charles was hiding on the battlefield and could not give orders. Note roman legions really would not suffer this issue.
- Your experienced commander had a definite effect on Tagliacozzo. But only on 1 section of the battlefield. And it's a section where all the elite troops are. Only elite soldiers could perform disengaging and false retreats. It's something no army on the whole achieved in medieval Europe.

Agincourt and Marshal D'Albert:
We'll never know what orders he gave beyond the initial order to his Flemish crossbows to engage. The problem (again) is that history is written by the victors, and he died in battle. So we never know what orders he gave, etc. But even if he tried, take the political side into account. The French knights were nobles of higher rank than him. This was an era where the French continued to view war as a "gentleman's game". Do you think those French knights would obey him?
It's highly unlikely. It would take loss after loss, and being driven to their knees, before they started to get a glimpse of the importance of military chain of command. French knights were notorious for their wild impetuous charges, and they lost battle after battle because of it.

Your additional examples:
They were all essentially issues of pre-positioning, and orders given before the battle. That's the critical point and difference. Roman commanders could give orders during the battle to any section of the battle. In a set piece battle, this can be the key to victory.

Again, strategy vs tactics.
Or maybe I need to split this into 3 sections:
1. Global strategy (terrain, army positioning, etc.)
2. Battle strategy (pre-positioning troops to ambush, etc.)
3. Battle tactics (orders given during combat to increase effectiveness. Like taking advantage of a faltering section of the enemy line).
Medieval generals could apply global strategy and battle strategy. They could not apply battle tactics (except on a small section of the battle).

Mongolian horse archers:
it's not hard actually. hook it up to the saddle. But I was incorrect. Mongolian horse archers carried sabers in the eastern nomadic tradition, not spears.
Either way, mongolian horse archers were superb horse archers and light cavalry, so they had no weaknesses. What they couldn't outfight, they could outrun. What could fight them equally, they could lure into ambushes. The only weakness of the mongolian horse archers were archers.

But this is completely off-topic (and really is supposed to belong in another thread)

About castles (and mongols):
Final OT point.
Good point on stone castles. All castles of the east were wooden ones.
And they conquered Persia's towns with the use of chinese siege engineers, who they didn't have in the invasion of Europe.
Could you link me to the Battle of Muhi thread?

Also, beating someone with superior numbers doesn't prove that you are a genius level general, or a superior soldier.

Actually, being a genius level general comes down to whether you win or not. In order to win and continue to win, conservation of forces is the critical point.

Alexander conquered the world with an incredibly small force, because the equipment of his army meant his casualties in battle were always low.
The Romans conquered the world because their discipline and tactics let them extract their army out of any situation where they were being outfought. The disasters occurred when they couldn't do that: Carrhae, Cannae, and Adrianople.
All of these situations occured because of cavalry. It was these disasters that led to the conclusion that cavalry is better than infantry (which it is).

Civil war general Nathan Bedford Forres summed this up in 1 quote: "Get there the fastest with the mostest".

This was also the genius of the Mongolian armies. Mongols horse archers never engage in the melee unless they outnumber their enemy by a significant margin at the point of contact, so casualties are always low.
So every battle they fight was actually numerous skirmishes where they always outnumber their enemy.

Beginning with 20000 troops, and going up to 80,000 or so, the mongols conquered the world.
And that is why Genghis Khan and his subordinate generals: Subotai are considered military geniuses.
They won their battles by completely outnumbering the enemy at point of contact. So even though their armies were (on a global level) small, they never truly lost any battles, so they never suffered any disasterious defeats like the Romans did.

On a side note, that's also the brilliance of the German blitzkrieg. They lost WW2 when they were forced into trench-style warfare, and the attrition just slowly but steadily defeated them.

Eric:
That's far to simplistic.
1) cities are the lifeblood and economy of any country. Castles are ultimately tiny. You cannot fit the population of any city in a castle in addition to your soldiers. And if you try, you would run out of food very quickly. It's impossible.

2) If the mongols razed all these cities, the economy of europe would be shattered. Life would not go on, because there would be nowhere for people to make their living (assuming they haven't been killed when the mongols plundered their way through Europe).

3) Raze enough cities, and the people would surrender and fall under your rule. That's what happened in China and Persia. The mongols could of made that happen in Europe.

As an example take a look at Vietnam after the Vietnam war. Yes, the Americans lost the war. But Vietnam's cities and economy was so utterly devastated by the war the people there spent the last few decades in poverty. It's only recently that their economy has started to swing up. But the common person living there is still in poverty.


edit:
But back to the original point (and conclusion):

The reason I put my money on a roman legion over a medieval army is ultimately this:
If a medieval army loses a major battle, it disintegrates. They rout, the enemy cavalry pursues and kills a significant number of them.
By comparison, a roman army will remain disciplined and hold firm, and retreat in good order. Even if they lose, the army will survive and fight another day. Sooner or later, the medieval army will lose a battle, at which point, the medieval army will disappear completely.

The problem, however, is that medieval heavy cavalry can rout a roman army. Note that if the roman army was equipped so that heavy cavalry cannot rout them, the roman army would slaughter the medieval army in every scenario, hands down..

[Last Roman]

No Mongols could not of conquered Europe. Castle, after castle, after heavily fortified castle would of prevented that. The hundreds upon hundreds of fortified positions the Europeans had would of prevented the Mongols from conquering. Sure, they could overrun the land, but they would never be able to conquer the castles with their form of warfare, which emphasized speed and shock. They would become bogged down in a battle of attrition with the European castle-dwellers which they could not win. A battle of attrition that the Mongols would have to fight to take a castle would remove their speed and they would be doomed, basically. Eventually they would be forced to withdraw, exhausting their supplies and men from throwing them in waves against the rocks that were Medieval castles.

I disagree. As seen in Asia and the Middle East, the Mongols were very capable of taking over cities and fortresses. If the Mongols had the numbers and motivation to take over (much of) Europe, they could've. The only reason they stopped at Hungry was because of internal problems.