Herodian (late second, first half third century): Greek historian, author of a History of the Roman Empire since the Death of Marcus Aurelius in which he describes the reign of Commodus (180-192), the Year of the Five Emperors (193), the age of the Severan dynasty (211-235), and the Year of the Six Emperors (238).
The translation was made by Edward C. Echols (Herodian of Antioch's History of the Roman Empire, 1961 Berkeley and Los Angeles) and was put online for the first time by Roger Pearse (Tertullian.Org). The version offered on these pages is hyperlinked and contains notes by Jona Lendering.
Peace with Parthia
[4.15.1] [Summer 217] Artabanus [IV] appeared at sunrise with his vast army. When they had saluted the sun, as was their custom, the barbarians, with a deafening cheer, charged the Roman line, firing their arrows and whipping on their horses. The Romans had arranged their divisions carefully to insure a stable front; the cavalry and the Moorish javelin men were stationed on the wings, and the open spaces were filled with light-armed and mobile troops that could move rapidly from one place to another. And so the Romans received the charge of the Parthians and joined battle.note[Near Nisibis.]
[4.15.2] The barbarians inflicted many wounds upon the Romans from above, and did considerable damage by the showers of arrows and the long spears of the mail-clad dromedary riders. But when the fighting came to close quarters, the Romans easily defeated the barbarians; for when the swarms of Parthian cavalry and hordes of dromedary riders were mauling them, the Romans pretended to retreat and then they threw down caltrops and other keen-pointed iron devices. Covered by the sand, these were invisible to the horsemen and the dromedary riders and were fatal to the animals.
[4.15.3] The horses, and particularly the tender-footed dromedary, stepped on these devices and, falling, threw their riders. As long as they are mounted on horses and dromedary, the barbarians in those regions fight bravely, but if they dismount or are thrown, they are very easily captured; they cannot stand up to hand-to-hand fighting. And, if they find it necessary to flee or pursue, the long robes which hang loosely about their feet trip them up.
[4.15.4] On the first and second days the two armies fought from morning until evening, and when night put an end to the fighting, each side withdrew to its own camp, claiming the victory. On the third day they came again to the same field to do battle; then the barbarians, who were far superior in numbers, tried to surround and trap the Romans. The Romans, however, no longer arranged their divisions to obtain depth; instead, they broadened their front and blocked every attempt at encirclement.
[4.15.5] So great was the number of slaughtered men and animals that the entire plain was covered with the dead; bodies were piled up in huge mounds, and the dromedaries especially fell in heaps. As a result, the soldiers were hampered in their attacks; they could not see each other for the high and impassable wall of bodies between them. Prevented by this barrier from making contact, each side withdrew to its own camp.
[4.15.6] Macrinus knew that Artabanus was making so strong a stand and battling so fiercely only because he thought that he was fighting Caracalla; the barbarian always tires of battle quickly and loses heart unless he is immediately victorious.
[4.15.7] But on this occasion the Parthians resolutely stood their ground and renewed the struggle after they had carried off their dead and buried them, for they were unaware that the cause of their hatred was dead. Macrinus therefore sent an embassy to the Parthian king with a letter telling him that the emperor who had wronged him by breaking his treaties and violating his oaths was dead and had paid a richly deserved penalty for his crimes. Now the Romans, to whom the empire really belonged, had entrusted to Macrinus the management of their realm.
[4.15.8] He told Artabanus that he did not approve of Caracalla's actions and promised to restore all the money he had lost. Macrinus offered friendship to Artabanus instead of hostility and assured him that he would confirm peace between them by oaths and treaties. When he learned this and was informed by envoys of Caracalla's death, Artabanus believed that the treaty breaker had suffered a suitable punishment; as his own army was riddled with wounds, the king signed a treaty of peace with Macrinus, content to recover the captives and stolen money without further bloodshed.
[4.15.9] The Parthian then returned to his own country, and Macrinus led his army out of Mesopotamia and hurried on to Antioch.