I have heard and read it time and time again: Roman cavalry was terrible. It was only good at riding down enemy troops that had already routed. The Romans neglected their cavalry and therefore lost important battles. And because of this neglect, they were ultimately unable to fight off foreign invaders, thus bringing about the end of the Roman Empire in the West. No matter how many times you hear or read a bad story, it never gets any better. In fact, it only gets worse.
People will usually relate how the Roman cavalry was destroyed at Cannae in 216 BCE. True, but it was outnumbered anyway and outperformed by an experienced enemy that had been in the field for years. Fourteen years later, it would be the other way round at Zama. People will relate how Crassus’ legions were annihilated at Carrhae by the Parthians in 53 BCE. True again, those legions did not stand a chance against the combination of horse archers and heavy cataphract cavalry. But the Romans learned from their mistakes and in 39 and 38 BCE, Publius Ventidius Bassus’ army used clever tactics to destroy two Parthian armies mostly made up of cavalry. Sure, the Roman army of Valens was obliterated by the Goths at Adrianopolis in 378, but today few still support the theory that this was because of the dominance of ‘Gothic knights’ – I quote Sid Meier’s Civilization – on the battlefield. The Gothic cavalry did play a role, but the scorching heat, the legionaries’ heavy armour, the ineptitude of the emperor Valens (who refused to wait for reinforcements) and the ill discipline in some parts of the army were certainly more important.
The truth is, the Romans fully understood the value of good quality cavalry. And they also had plenty of ways to counter and defeat enemy armies that were more cavalry-heavy than their own.
The Roman horsemen
It is true that the legions, that is: that part of the Roman army that was made up of Roman citizens, was relatively weak with regard to the cavalry. The Roman equites in the Republican legions were selected because of their wealth, not because of their skills and experience. Combined with the fact that the Romans were not exactly “born in the saddle”, it made them somewhat mediocre horsemen, although they were certainly brave and eager for glory. After the Marian reforms, the 200-300 horsemen that accompanied each legion were abandoned (together with the light troops called velites) and the legions focussed chiefly on heavy infantry (although an imperial legion usually had up to 120 horsemen for scouting and screening duties, the “legionary cavalry”).
But a Roman army was not just made up of Roman legions. During the early to late Republic it was supported by alae (wings) of allied infantry and cavalry. During the Empire, cohorts of allied foot and horse (cohors pedita and cohors equitata) also served in the Roman army, as did alae (again wings, but now only referring to the cavalry) of well-equipped auxiliary horsemen. The Romans simply focussed on what they were best at, which was heavy infantry, and let their allies (socii, auxilia or foederati) play the supporting role with regard to missile troops and cavalry. Excellent Numidian, Moorish, Gallic, Celtiberian and Germanic cavalry served in the Roman army, and was later joined by elite horsemen from Pannonia and Sarmatia. Caesar relied heavily on his Gallic and Germanic cavalry during his conquest of Gaul and Roman emperors usually had a personal mounted bodyguard made up of elite provincials or allies, the equites singulares augusti. In the army of the late Empire, the Romans also included cataphracts and clibanarii in their field armies and they even experimented with cataphract chariots.
Stopping enemy cavalry
It needs to be said: you do not need cavalry to destroy the enemy cavalry. When fighting against cavalry-heavy enemies, such as the Parthians, the Romans usually sent in armies consisting of the heavy legionaries supported by many missile troops – archers and slingers, sometimes horse archers – and light cavalry. The legions would march in a hollow square, which could fend off attacks from every side. It would be screened by the missile troops and cavalry, which could find refuge within the square if they were charged by Parthian cavalry. Even cataphracts will not charge a fully intact wall of shields. The Roman auxiliary foot archers could usually outshoot the Parthian horse archers and the slingers could even give cataphracts a concussion. This is what Cassius Dio had to say about Ventidius Bassus’ victory over the Parthians in 38 BCE:
“But when a sally [i.e. by the Romans] was suddenly made, the assailants [i.e. the Parthians], being cavalry, were driven back down the slope without difficulty; and although at the foot they defended themselves valiantly, the majority of them being in armour, yet they were confused by the unexpectedness of the onslaught and by stumbling over one another and were defeated by the heavy-armed men and especially by the slingers; for these struck them from a distance with their powerful missiles and so were exceedingly difficult for them to withstand.”
This tactic worked really well and under several emperors (Trajanus, Lucius Verus, Septimius Severus, Carus, Galerius), the Romans were able to ravage the Parthian and later the Sassanid territories and sack their capital Ctesiphon. The Romans also developed a formation sometimes called repellere equites (repel horsemen) and described by Greco-Roman general and statesmen Arrianus (the man who also wrote a famous biography of Alexander the Great). It basically involved the soldiers in the front ranks kneeling behind their shields and holding up their pila at a 45 degrees angle to form a wall of sharp pointy things. A horse simply will not charge that. The soldiers in the rear ranks would give weight to the formation and hurl their javelins at the charging horsemen, while archers and possibly horse archers provided additional missile support. Furthermore, the soldiers of the Roman army started to trade in their pila for thrusting spears from the third century onward. These spears (they may have been called lanceae, although that word was also used for a type of javelin) may have differed not all that much from the hastae which the early Republican armies used.
A balanced army
Just because the Romans gave a supporting role to the cavalry does not mean they ignored the importance of this part of the army. The Romans fully understood the need for a balanced army composed of both infantry and cavalry throughout the existence of both the Republic and the Empire. They also understood that not being a horse people themselves, they needed to call upon their allies and conquered peoples to provide them with the necessary horsemen. Alae of auxiliary cavalry and cohortes equitatae had very good quality horsemen that provided invaluable services to the Principate and were usually well paid, especially the alae. I can mention Titus and the siege of Jerusalem in 70, where his auxiliary cavalrymen and equites singulares continuously routed the Jewish defenders who gave his legions such a hard time. I can mention Hadrian’s inspection tour throughout the Empire and the equestrian exercises he witnessed in Africa, where horsemen conducted difficult tactical manoeuvres. I can mentioned Arrianus’ expeditions in 135 against the Alans, who fielded heavy cavalry which the Roman general managed to defeat. The Romans fully understood the need for strong cavalry forces, while at the same time focussing on their own speciality: the infantry. And that infantry had plenty of ways to deal with enemy horsemen themselves.
Fighting off invaders
It is quite true the Roman legions with their 5.000 men were not efficient in dealing with border raids. That had nothing to do with their quality or professional skills. It had everything to do with their size. I have discussed this previously. A legion is good for pitched battles, but those were rare in the second and third century. ‘Barbarian’ invasions were at first mainly border raids. Military reforms by Diocletianus and Constantine the Great focussed on much smaller and more mobile legions of no more than 1.000 men. Most of these were made up of provincials, as many Italians (the ‘true’ Romans) were reluctant to serve in the legions. A distinction was made between the border troops (limitanei) and the more mobile field armies (comitatenses, who I believe were not cavalry; if they had horses they were more likely mounted infantry). Constantine disbanded the Praetorian Guard (including the equites singulares) and created the new scholae palatinae, who were elite cavalry, but no more elite than the disbanded singulares. According to noted military historian Adrian Goldsworthy, the Romans of the fourth century excelled at low-level warfare, locating small bands of barbarian raiders, tracking them down and destroying them as they tried to get away with their loot (which made them considerably less mobile).
I do not think there is any evidence that the Germanic peoples that tried to cross the borders of the Roman Empire in the fourth century were better organised, equipped or trained or were more technologically advanced than, say, the Marcomanni or Quadi who tried to invade Roman territory in the days of Marcus Aurelius or even the Cimbri and Teutones who invaded in the late second century BCE. They were still loose confederacies of related peoples and according to Goldsworthy, their military organisation had changed very little from the first to fourth century. Their small raiding parties may have been mobile, but their large scale invasions with wives, children, cattle and wagons were certainly not, so I really do not see how mobile cavalry-heavy armies could have countered those. The exception to the rule were probably the Huns, who employed a completely different way of fighting. But even their invasion was ultimately bogged down in France because of the heavy siege equipment they carried with them. They were cornered on a field near Chalons where they could not make full use of their cavalry and were defeated by a Roman-Gothic army in 451.
The most significant factor in the decline of the Roman Empire has, in my honest opinion, little to do with the value of cavalry or the decline of the Roman military. The Empire was weak on the inside. Emperors rose and fell, sometimes in the same year. Civil strife was everywhere and competent rulers were scarce. Many times the emperors used their armies against pretenders, usurpers and brothers who claimed the throne. Regions that were neglected by the emperor chose to govern themselves and foreign peoples that were allowed to settle on Roman soil (such as the Goths in Southern France) established autonomous kingdoms. It was internal weakness, much more than external threats, that ultimately caused the fall of the Roman Empire in the West.
- Bernard van Daele, Het Romeinse leger;
- Adrian Goldsworthy, The Complete Roman Army;
- Adrian Goldsworthy, In the Name of Rome.