Tactics and Deployment
While they varied in design and appearance, cataphracts were universally the heavy assault force of most nations that deployed them, acting as "shock troops" to deliver the bulk of an offensive manoeuvre, while being supported by various forms of infantry and archers (both mounted and unmounted). While their roles in military history often seem to overlap with lancers or generic heavy cavalry, they should not be considered analogous to these forms of cavalry, and instead represent the separate evolution of a very distinct class of heavy cavalry in the Near East that had certain connotations of prestige, nobility and esprit de corps attached to them. In many armies, this reflected upon social stratification or a caste system, as only the wealthiest men of noble birth could afford the panoply of the cataphract, not to mention the costs of supporting several war horses and ample amounts of weaponry and armor.
Fire support was deemed particularly important for the proper deployment of cataphracts. The Parthian army that defeated the Romans at Carrhae in 53 BC operated primarily as a combined arms team of cataphracts and horse archers against the Roman heavy infantry. Archer fire was concentrated on the dense Roman ranks, which prompted the legionaries to loosen their formation in order to present a wider target area for the enemy. This then made them fatally susceptible to a massed cataphract charge. The end result was a far smaller force of Parthian cataphracts and horse archers wiping out a Roman cohort four times their size numerically, due to a combination of fire and movement, which pinned the enemy down, wore them out and left them vulnerable to a concluding deathblow.
The cataphract charge was very effective due to the disciplined riders and the large numbers of horses deployed. As early as the 1st century BC, especially during the expansionist campaigns of the Parthian and Sassanid dynasties, Eastern Iranian cataphracts employed by the Scythians, Sarmatians, Parthians and Sassanids presented a grievous problem for the traditionally less mobile, infantry-dependant Roman Empire. Roman writers throughout imperial history made much of the terror of facing cataphracts, let alone receiving their charge. Parthian armies thus repeatedly repelled Roman incursions across the Euphrates, due in large part to the Roman's ineptness in dealing with mobile warfare and particularly cataphracts.
Persian cataphracts were a contiguous division known as the Savaran (Persian: سواران, literally meaning "rider of the horse") during the era of the Sassanid army and remained a formidable force from the 3rd to 7th centuries until the collapse of the Sassanid Empire. Initially the Sassanid dynasty continued the cavalry traditions of the Parthians, fielding units of super-heavy cavalry. This gradually fell out of favour, and a "universal" cavalryman was developed during the later 3rd century, able to fight as a mounted archer as well as a cataphract. This was perhaps in response to the harassing, nomadic combat style used by the Sassanids' northern neighbours who frequently raided their borders, such as the Huns, Hephthalites, Xiongnu, Scythians and Kushans, all of which favoured hit and run tactics and relied almost solely upon horse archers for combat. However, as the Roman-Persian wars intensified to the West, sweeping military reforms were again re-established. During the 4th century, Shapur II of Persia attempted to reinstate the super-heavy cataphracts of previous Persian dynasties to counter the formation of the new, Roman Comitatenses, the dedicated, front-line legionaries who were the heavy infantry of the late Roman Empire. The elite of the Persian cataphracts, known as the Pushtigban Body Guards, were sourced from the very best of the Savaran divisions and were akin in their deployment and military role to their Roman counterparts, the Praetorian Guard, used exclusively by Roman Emperors. Ammianus Marcellinus remarked in his memoirs that members of the Pushtigban were able to impale two Roman soldiers on their spears at once with a single furious charge. Persian cataphract archery also seems to have been again revived in late antiquity, perhaps as a response (or even a stimulus) to an emerging trend of the late Roman army towards mobility and versatility in their means of warfare.
In an ironic twist, the elite of the East Roman army by the 6th century had become the cataphract, modelled after the very force that had famously defeated and slaughtered their forebears numerous times more than 500 years earlier. During the Iberian and Lazic wars initiated in the Caucasus by Justinian I, it was noted by Procopius that Persian cataphract archers were adept at firing their arrows in very quick succession and saturating enemy positions but with little hitting power, resulting in mostly non-incapacitating limb wounds for the enemy. The Roman cataphracts, on the other hand, released their shots with far more power, able to launch arrows with lethal kinetic energy behind them, albeit at a slower pace.
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