How did Trajan defeat the Parthians?

[Vitapondera]

Any idea what tactics were used to defeat the Parthians? Most histories on the subject talk about Parthian's internal strife, inability to field large armies for extended periods of time (their warriors being more like knights than soldiers), and the like. But tactically how did Roman infantry and cavalry defeat the horse archers and cataphracts?

Thanks!

[Matthew Amt]

Ave!

Well, the horse archers aren't all that hard to beat, since Roman cavalry typically has armor and shields. They can close to javelin range without many casualties and do bad damage to the unarmored Parthians. Crassus' cavalry at Carrhae did that, they just over-pursued and got themselves cut off and slaughtered. (Oops.)

The cataphracts are a slightly tougher nut to crack, but my guess is that Trajan (and other commanders) simply hired other cataphracts from the eastern areas. Combined with other Roman heavy cavalry, that would probably do the trick.

Remember that the Roman cavalry always had their infantry as a nice solid line to fall back on to regroup, whereas the Parthian army was entirely mounted. If their cavalry couldn't stop those legionaries cold, the Romans could simply walk right up to and through the Parthian camp, capturing all the baggage, provisions, families, etc. There goes your army.

Also keep in mind that the Romans could march farther in a day than even a Parthian army. Sure, horses are faster on the battlefield, but a good infantry force can out-march a cavalry force. Keep beating and starving good legionaries, and they'll keep marching for you. Mistreat a horse or try to force-march one, and it will promptly die out of spite! So apparently the Parthians were always terrified about being surprised in their camp by the Romans, so they tried to be more than a day's march from them when they camped. Naturally, that meant a couple days of trying to catch up with the Romans again, or even losing them altogether!

Other than that, the basic rules in Parthia were to keep off the flat open ground if possible, make sure you have a good line of supply with access to water and food, and keep your cavalry under control. Oh, and keep behind that shield, legionary!

Vale,

Matthew

[Gaius_Calvus]

Good question.

Taking another look at this from more than a cavalry vs cavalry perspective, here are some ideas.

A well-balanced Roman Army of close-order infantry, loose-order missile troops, cavalry and artillery presents a cavalry-heavy Parthian army with a multitude of problems if handled effectively. Horses, even cataphracts, will not charge home against an obstacle like that presented by a steady, formed body of troops like a legionary cohort. Cavalry can only succeed against this formation if the infantry's morale breaks prior to or at contact, letting the cavalry break their ranks (or if they can envelop the infantry). (Keegan gives a superb analysis of this phenomenon in his "Face of Battle.")

So, the Parthians -- with no comparable infantry to speak of -- going up against the Romans have a problem. If they cannot wear down the legionaries with missile fire from horse archers, creating physical or moral gaps in in their formations, then they cannot bring their "shock" cavalry to bear in order to achieve a tactical decision.

On the Roman side, their advantage was that their army was much more of a combined arms force, which relied on complementary and reinforcing combined arms effects to achieve tactical, battlefield success. Matt alludes to this above when he mentions that the Roman infantry was able to serve as a shield to support the ability of their cavalry to reform. Likewise, cavalry secures the infantry flanks/rear from Parthian cavalry envelopment. Having said this, combined arms effects go much farther toward ensuring success.

Complementary combined arms effects are achieved when one places the enemy on the horns of a dilemma -- forcing him to react to multiple, simultaneous threats that have no single right answer due to the variety of problems they present.

Thus, the Parthians could be threatened with foot missile fire (which would outrange their mounted archers), close/loose order foot, cavalry and artillery at the same time. Even if the Roman Army never achieved a decisive battlefield defeat of the Parthians, the Parthian inability to inflict the same on the Romans meant that the Romans could practice another, familiar type of warfare -- attrition warfare -- that they used against the Gauls, Britons, and other opponents. Raiding, burning crops/villages/towns, etc as they marched toward various Parthian centers of gravity -- like their major cities and centers of government.

So, it could very well be that Trajan was successful because he could, by virtue of preventing a tactical Parthian victory (due to his ownership of a disciplined, combined arms army) achieve operational/strategic victory by avoiding tactical defeat.

Had the Parthians defeated Trajan like they defeated Crassus, this battle of annihilation (vernichtungschlact) would have ended the war. Likewise on Trajan's part. It thus seems likely to me that the following occurred:

1) As Matt states, the Romans enjoyed greater operational mobility (could maintain a greater rate of advance than the Parthians).

2) The Parthians had greater tactical mobility (on the part of their cavalry).

3) As long as the Romans maintained their discipline and combined arms mix (if I recall correctly, Crassus' cavalry was destroyed and/or deserted him in the case of his Skenite Arabs), then the Parthians are not able to force a battle of annihilation. Neither, however, are the Romans able to do so given the greater tactical mobility of the Parthians.

4) The Romans, therefore, opt to pursue a strategy of attrition -- burning, pillaging, besieging cities/strongholds, etc.

5) Cumulatively, the Parthians are weakened physically and morally, while simultaneously unable to achieve a decisive tactical success, leaving them the losers in the conflict.

At any rate, this is my opinion. No major battles from Trajan's Pathian Campaign on the order of Carrhae seem to be documented, so I think my analysis holds water in light of the evidence.

Vale,

Calvus

[mars]

There was several reasons:
1. under the ruling of Trajan, Rome was in her golden age, her army was very powerful, and Trajian
himself was an excellent generals
2. Pathia was in her low ebb, at her east border, the war between Pathia and Kushan Empire had last
more than 100 years, and in the first century, Pathia was repeatly defeated by Kushan suffered huge
losses from both manpower and land, Pathia also had to fight Central Asia Normandic tribes who would raid
their East regions every year, Pathia was exhausted
3. there was a civil war in the Parthia which lasted more than 10 years when Trajan invaded, Trajan only
need to fight the west part of Pathia
4. the power of Parthia king was already in decline, many of his Lords simply ignored king's order,
this was the reason Parthian failed to field an army agains Roman when Trajan invaded, Parthian king himself had
no army ! and only after Roman tried to convert western Parthian to a Roman province, then Parthian
rose in mass

[Jona Lendering]

Personally, I think Trajan did not defeat the Parthians. Yes, he overcame them briefly, sacked Ctesiphon and even reached the Persian Gulf, but he was unable to cross the Zagros and invade the Parthian heartland. The sack of Ecbatana or Hecatompylus was never contemplated by the Romans, and the territories they had been able to occupy, they eventually gave up because there were insurrections, which were blamed on the Jews.

It's not unlike Alexander's attack on the Punjab: he sacked a coupla towns, defeated every enemy, but was unable to control the country, and before his reign was over, the Macedonians had already abandoned positions in Sind.

[Goffredo]

By the same logic the parthians never defeated the romans and neither did the sassanians! Poor Shapor I! He made all that havoc in the roman east and by the same logic we saying he never defeated the romans!

How about denying Alexander the Great his greatness. Persia's armies were easy to defeat! They were not as compact and motivated as the macedonian one. The real enemy was distance, weather and unpredictables, certainly not the persian armies! Almost a piece of cake!

The same arguements that are made to deny Trajan glory could be used to deny Shapor's victories. The roman were over-strectched hence easy to beat. The roman emperors were weak due to risks of coups hence easy to beat. The romans were thin in defending the easter provinces hence east to beat. Bla bla bla. Shapor was fantastic and beat = defeated the romans bad. Trajan did a good job too as did other roman emperors and generals. And Alexander was the best of them all.

I think this watering down of concepts and words that originally had obvious and down to earth meanings to the absurd point of making them useless is sterile (= useless).

[Robert Vermaat]

By the same logic the parthians never defeated the romans and neither did the sassanians! Poor Shapor I! He made all that havoc in the roman east and by the same logic we saying he never defeated the romans!

Jeffrey, hold your horses!
I think Jona made a simple mistake by confusing the words 'conquer' and 'defeat'.
Jona, if you meant that the Romans never conquered the Parthians, you are right.
Jeffrey, if you mean that the Romans defeated the Parthians, etc. you are right.

Only the Parthians were conquered by the Sassanid Persians, as Alexander had conquered the Achaemenid Persians before that.
Rome never conquered Parthians nor Persians, but the latter were conquered by the Muslim Arabs as the Byzantines were conquered by the Muslim Turks.

And then they all ran out of conkers.

But the original question was how Trajan defeated the Parthians (on the battlefield I therefore presume). Maybe we'de best look at how Arrian defeated (planned to) the Alans for that?

[Robert Vermaat]

Well, the horse archers aren't all that hard to beat, since Roman cavalry typically has armor and shields. They can close to javelin range without many casualties and do bad damage to the unarmored Parthians. Crassus' cavalry at Carrhae did that, they just over-pursued and got themselves cut off and slaughtered. (Oops.)

Not that hard to beat? Well, I doubt that it was ever easy, since (as you may see in RTW), lighter cavalry can never really be caught by not-so-light cavalry. The armour and shields work well in defense, but if you can't close with them you can only drive them off. I don't agree that you can get close without too many casualties, btw. Even if possible, the horse archers would evade, tempting you to go in pursuit. Which always carries the risk that you're cut off from your support infantry. Bad idea.

The cataphracts are a slightly tougher nut to crack, but my guess is that Trajan (and other commanders) simply hired other cataphracts from the eastern areas. Combined with other Roman heavy cavalry, that would probably do the trick.

Armenian cataphracts, always a good idea as support troops, but a steady line of infantry works far better. Cataphracts only work with effect when the infantry is in disarray (softened up by the horse archers is the idea), but they are not a steady force. As Later Roman armies showed (and which Arrian already theorised about) is that heavy infantry, even heavily outnumbered) can hold against vastly superior number of (armoured) cavalry. Even better when they are supported by plenty of missile troops, as the Romans learned after Carrhae. And as Arrian advised, once you have them on the run (they tire easily and can't do much of the surprise wheeling tactic), that's when you let the cavalry loose after them.

Remember that the Roman cavalry always had their infantry as a nice solid line to fall back on to regroup, whereas the Parthian army was entirely mounted. If their cavalry couldn't stop those legionaries cold, the Romans could simply walk right up to and through the Parthian camp, capturing all the baggage, provisions, families, etc. There goes your army.

Indeed, which is why Roman infantry developed into a redoubt for ever growing numbers of cavalry - most likely the Eastern Wars were the cause for that.

Also keep in mind that the Romans could march farther in a day than even a Parthian army. Sure, horses are faster on the battlefield, but a good infantry force can out-march a cavalry force.

Not entirely correct, infantry does not outmarch cavalry in a day, but in three, after when the difference becomes ever larger.

[Jona Lendering]

I think Jona made a simple mistake by confusing the words 'conquer' and 'defeat'.

Yep. :oops:

[L C Cinna]

It was a strategic victory for the Romans I'd say. Roman warfare was quite different from let's say hellenistic warfare. They didn't necessarily search for a big decisive battle.

In greek, hellenistic conflicts decisions were sought in one decisive battle. The wars between the Seleucids and the Lagides are some good examples for that. The battles weren't even fought to the bitter end because each side needed the mercenaries and professional soldiers so it was quite common that the phalanx of one side just lifted their sarissae when they thought the battle to be lost and everyone returned home. This changed when the Romans first entered the east because of their willingsness to make a victory decisive by destroying as much of the enemy as possible and by actually destroying the enemy's land, towns whatever. Roman warfare was quite modern in that aspect and when you look at HOW the Romans fought their wars you will see that their main goal always was a strategic victory much more than a victory on a specific battlefield. The building of camps, fortresses, streets, engineering were as, if not more important than fighting a battle.

This didn't really change, of course equipment changed and each enemy and area required different operations but in general the way the army operated during the empire stayed the same.

it can be found in Caesar, although he often accepts or forces battles much more than other Roman commanders would.

best examples for Roman warfare are Tacitus description of Germanicus campaign and Josephus Judaean war. to sum it up: systematically destroying the countryside and important settlements, secure important places, if the enemy offers battle and you feel secure accept it, if you don't, hit him where he can't protect his property or people and stay on the safe side yourself (some ppl like Crassus or Varus neglected that and got defeated). The Romans really started this kind of warfare after their defeats in the 2nd punic war when they realized that they can win the war even without being able to beat Hannibal in the field. They took the war to Spain and Africa.

Ok this might all seem a bit far-fetched and has nothing to do with the actual Parthian campaign but imho there's always ONE concept behind most Roman operations and once you see it from that perspective it gets much clearer. Why risk a battle if you can defeat the enemy in other ways without losing as many soldiers?

So what Germanicus did was use the strenght of the Roman army: engineering, secured supply, speed and transport to devastate the Germanic areas.

Vespasian and Titus did the same. They knew the Judaeans are not able to offer battle so they devastated and captured their strongholds without which they couldn't resist.

Traian knew where the strenght of his army lay. Speed, engineering, heavy infantry and heavy cavalry to protect them. and he knew that the enemy was able to harrass his army while marching but not to offer battle or seriously harm his army as long as he could defend his supply line (something Antonius had failed in). So as long as he manages to keep his army together he could march through Parthian lands, sack, destroy and devastate without too much trouble.

Septimius Severus did the same 80 years later.

and although it is a later period, equipment had changed and we have the Sassanides instead of the Parthians I would suggest to read Ammianus account of Iulianus Parthian war. He did the same as Traianus and Severus had done except that his 2nd column failed in meeting up with him (rather some kind of betrayal than his fault), the strange decision to burn the supply ships and to take another route and the tragedy of Iulianus death which led to the failure of the operation. but still I don't think Traian's campaign 200 years earlier was carried out in a much different way.

[mars]

Cinna, there are two things you shall consider:
1, Parthian and later Sassanides had a super calvary, the quality of their calvary was always better than Roman's, all cause Roman had the advantage of infantry and navy, talk the engineering troops, Parthian had virtually no engineer in their army, but Sassanides improved their engineering skill so much that became equal to Roman's. Parthian/Sassaindes was the only army in the "Roman world" that had the ability and not afraid to faced Roman army in the field, especially for Parthian, in most case, they could only field an army far smaller then Romans, but they were excellent soldiers, as far as they united together, they would not afraid Romans, Roman invasion of Parthia could only success when there was internal turmoil inside Parthia. Otherwise, Roman invasion always ended in defeat.
2. from the long term, I do not think it was a good idea for Romans to invade Parthia after 2 century, because, at that time, Parthia king had lost most of his authority, his kingdom was in turmoil, and his Lords and noblemen were more interesting in endless in-fighting, the Parthia Empire was already done for, but because of tradition, Parthia noblemen still recorgnized the king, who was so weak that he could post no real threat to Rome's east provinces, but Roman's invasion changed that, since the Parthian king was proved to be uttely unable to protect his kingdom and then lost most of his reputation among his noblemen and his people, and the losses Romans inflicted on Parthian made them realised that the only way to survied was to united together, that paved the way for the rebellion
led by Sassanid, who overthrown Parthian kindom and became a far more deadly enemy of Romans

[L C Cinna]

1st I don't think there's too much difference concerning cavalry during the Imperial periode. Of course the Parthians and Sassanides used more cavalry. They had an advantage concerning horse archers and heavy cavalry, something which changed during the dominate when the Romans used more heavy cavalry on the other hand the Romans had excellent medium cavalry. So I'd say the differences are not too big especially during the Sassanid era.

The Parthians couldn't and wouldn't be able to meet the Romans in the field excepet for very few occasions. Their hit and run tactics were a serious problem for all Roman armies which invaded and the Romans were neither able to nor planning to hold the terretories occupied.(i'm not trying to downgrade the Parthians or Sassanides here) but the wars between those 2 sides were decided by strategic actions all the time and neither side was interested in conquest. The Parthian empire was in a weaker position during the 1st and 2nd century, this changed when the Sassanides appeared which kind of made both sides equal.


2nd I didn't deny that. I agree that it was a political mistake to invade Parthia. The Parthian empire never was a thread to the Romans and it was a bad idea on the long term that Septimius Severus and immediately after him Marcus Aurelius invaded Parthia.

[mars]

1st I don't think there's too much difference concerning cavalry during the Imperial periode. Of course the Parthians and Sassanides used more cavalry. They had an advantage concerning horse archers and heavy cavalry, something which changed during the dominate when the Romans used more heavy cavalry on the other hand the Romans had excellent medium cavalry. So I'd say the differences are not too big especially during the Sassanid era.

The Parthians couldn't and wouldn't be able to meet the Romans in the field excepet for very few occasions. Their hit and run tactics were a serious problem for all Roman armies which invaded and the Romans were neither able to nor planning to hold the terretories occupied.(i'm not trying to downgrade the Parthians or Sassanides here) but the wars between those 2 sides were decided by strategic actions all the time and neither side was interested in conquest. The Parthian empire was in a weaker position during the 1st and 2nd century, this changed when the Sassanides appeared which kind of made both sides equal.


2nd I didn't deny that. I agree that it was a political mistake to invade Parthia. The Parthian empire never was a thread to the Romans and it was a bad idea on the long term that Septimius Severus and immediately after him Marcus Aurelius invaded Parthia.

Cinna, Parthian's calvary were consist with the heavily-armed and armoured cataphracts and lightly armed but highly-mobile mounted archers, no Roman heavy calvary could be match to Parthian cataphracts, those parthian were best heavy calvary in the Roman world. and I DO think you misunderstand the tradional parthian calvary tactics as "only hit & run", you know contract with infantry tactics, the advantage of calvary warfare was their ability to manoeuvre, when in an eye of Roman infantry, Parthian calvaryman was so coward that they dared not unmound their horse and fight him hand to hand, the Parthian calvarymen may also surprised that why those Roman were so stupid that stand there like a sitting duck, "why don't they manoeuvre like us ?"
before the invasion of Trajan, there were several clashed between Parthia and Roman, In 53 BCE, the first war between Roman and Parthian, 10,000 Parthian defeted 40,000 Roman army led by Marcus Licinius Crassus in the battle of Carrhae, in the second war between Roman and Parthia (41 BC - 39BC), Parthian invaded Rome's east provinces,
they defeated Roman's governer of Syria, but In 39 BCE, Roman General Publius Ventidius Bassus count-attacked and twice defeated Parthian army, those were the only Roman victories against Parthian before Trajan invasion, but please notice thatthe first of Bassus's victories was agains mostly those defected pro-republic Roman soldiers who defected to Parthia,and in the second battle in which Pacorus was killed,Bassus had 11 legions,Romans outnumbered Parthian at least 2 to 1,
in the third war between Rome and Parthia in the in 36 BCE, Mark Antony invaded Parthia with an army nearly 100,000 men, Parthia could only field an army less then 50,000 calvary, the result was that Antony was soundly defeated and lost near half size of his army, (for God's sake, PLEASE DO NOT tell me that, that was because those Parthian only used the "hit & run" tactic, if they stood their ground they would be easily defeated, well I guess a German tribleman could then say "those Roman army was no good, if they dare to take off their armor, throw away their shield, do not form to line, and come out one by one & fight like a man, they could
be very easily defeated, but those cowards simply dare not to do that")
The forth war between Roman and Parthian broke out in 60's, the result was two Roman legions was wipped out by Parthian in the Battle of Rhandeia in 62.
even after the decline of the Parthia Empire, defeated by Kushan Empire at east and suffered in the endless civil war, when Parthian could manage
to unite, they could still be an dangerous enemy,actually in the last major battle between Roman and Parthian, led by king Artabanus IV of Parthia, Parthia army soundly defeated Roman army at the battle of Nisibis in 217.
So yes, Parthian could fight Romans in field and sometimes they did win.

[L C Cinna]

I did not criticise the Parthian way of warfare and I didn't deny Crassus defeat.. Antonius lost his men on his retreat after he had not taken enough care to protect his siege train and supply lines and was forced to march back. As I said another strategic victory. this time for the Parthians. During the Principate however they were in a much weaker position than the Romans were because of internal problems and other reasons.

Rhandeia was a Roman defeat. Paetus was as incapable as Crassus was and got himself into a similar situation where he was surrounded and had to surrender still the war was won after Corbulo attacked. another strategic victory, this time for the Romans.

The only true Parthian victory during the empire was ironically their last at Nisibis in 217 against Macrinus.

As is said before I'm NOT saying the Parthians were stupid or cowards or whatever. I just say that since the reign of Augustus until their end they were never a real threat to the Romans. They were definately the weaker of those 2.

As for cavalry tactics> this depends pretty much on the situation. I already said that the Parthian cavalry was excellent. The Romans had nothing comparable to their horsearchers and their cataphracts were excellent heavy cavalry and parthian tactics relied on the combination of the 2...weakening enemy forces to break formation by using archers followed by an attack with the heavies. However this is not something which can be answered easily and depends on the situation. If the Parthians manage to neutralize the Roman cavalry as was the case at Carrhae this works fine. If this is not possible the cataphracts are out of the game as they are highly immobile and need to be protected against attacks from "medium" cavalry. Ammianus (if I remember correctly will look it up this weekend) gives a nice description of their advantages and disadvantages. They are perfect to break an infantry formation if it doesn't hold formation and they can exploit a gap. on the other hand they lose momentum rather quickly and become sitting ducks if they don't manage to route the enemy instantly and their use has to be well prepared as they can't perform actions covering longer distances.
btw don't underestimate Roman cavalry.

[mars]

Cinna, you shall know that, to Parthian, Kushan Empire was a far more dangerous enemy than Rome, the war between Kushan and Parthia lasted more than 100 years, and in east was most of Parthian's effort go, of course Parthian had to maintan defense in their west front, and when Parthian did not post real threat to Romans since since the reign of Augustus, but do you really think Romans post a real threat to Parthian before Trajan' reign ?


And you said "Rhandeia was a Roman defeat. Paetus was as incapable as Crassus was and got himself into a similar situation where he was surrounded and had to surrender still the war was won after Corbulo attacked."
first when you got defeated, of course your commander had some kind of problme, blah ! and whoa ! I read Roman history, but I DO NOT KNOW later Roman won that war after Corbulo attacked ! Actually Roman and Parthian struck a deal, so that Amenia king would come from Parthia, but he should be approved by Roman Emperor and Senate, did sound a military victory ?