Accession of Orodes I. Expedition of Crassus. His fate. Retaliatory inroad of the Parthians into Syria under Pacorus, the son of Orodes. Defeat of Pacorus by Cassius. His recall. End of the first War with Rome.
The complete triumph of Orodes over Mithridates, and his full establishment in his kingdom, cannot be placed earlier than B.C. 56, and most probably fell in B.C. 55. In this latter year Crassus obtained the consulship at Rome, and, being appointed at the same time to the command of the East, made no secret of his intention to march the Roman legions across the Euphrates, and engage in hostilities with the great Parthian kingdom. According to some writers, his views extended even further. He spoke of the wars which Lucullus had waged against Tigranes and Pompey against Mithridates of Pontus as mere child’s play, and announced his intention of carrying the Roman arms to Bactria, India, and the Eastern Ocean. The Parthian king was thus warned betimes of the impending danger, and enabled to make all such preparations against it as he deemed necessary. More than a year elapsed between the assignment to Crassus of Syria as his province, and his first overt act of hostility against Orodes.
It cannot be doubted that this breathing-time was well spent by the Parthian monarch. Besides forming his general plan of campaign at his leisure, and collecting, arming, and exercising his native forces, he was enabled to gain over certain chiefs upon his borders, who had hitherto held a semi-dependent position, and might have been expected to welcome the Romans. One of these, Abgarus, prince of Osrhoene, or the tract east of the Euphrates about the city of Edessa, had been received into the Roman alliance by Pompey, but, with the fickleness common among Orientals, he now readily changed sides, and undertook to play a double part for the advantage of the Parthians. Another, Alchaudonius, an Arab sheikh of these parts, had made his submission to Rome even earlier; but having become convinced that Parthia was the stronger power of the two, he also went over to Orodes. The importance of these adhesions would depend greatly on the line of march which Crassus might determine to follow in making his attack. Three plans were open to him. He might either throw himself on the support of Artavasdes, the Armenian monarch, who had recently succeeded his father Tigranes, and entering Armenia, take the safe but circuitous route through the mountains into Adiabene, and so by the left bank of the Tigris to Ctesiphon; or he might, like the younger Cyrus, follow the course of the Euphrates to the latitude of Seleucia, and then cross the narrow tract of plain which there separates the two rivers; or, finally, he might attempt the shortest but most dangerous line across the Belik and Khabour, and directly through the Mesopotamian desert. If the Armenian route were preferred, neither Abgarus nor Alchaudonius would be able to do the Parthians much service; but if Crassus resolved on following either of the others, their alliance could not but be most valuable.
Crassus, however, on reaching his province, seemed in in haste to make a decision. He must have arrived in Syria tolerably early in the spring but his operations during the first year of his proconsulship were unimportant. He seems at once to have made up his mind to attempt nothing more than a reconnaissance. Crossing the Euphrates at Zeugma, the modern Bir or Bireh-jik, he proceeded to ravage the open country, and to receive the submission of the Greek cities, which were numerous throughout the region between the Euphrates and the Belik. The country was defended by the Parthian satrap with a small force; but this was easily defeated, the satrap himself receiving a wound. One Greek city only, Zenodotium, offered resistance to the invader; its inhabitants, having requested and received a Roman garrison of one hundred men, rose upon them and put them barbarously to the sword; whereupon Crassus besieged and took the place, gave it up to his army to plunder, and sold the entire population for slaves. He then, as winter drew near, determined to withdraw into Syria, leaving garrisons in the various towns. The entire force left behind is estimated at eight thousand men.
It is probable that Orodes had expected a more determined attack, and had retained his army near his capital until it should become evident by which route the enemy would advance against him. Acting on an inner circle, he could readily have interposed his forces, on whichever line the assailants threw themselves. But the tardy proceedings of his antagonist made his caution superfluous. The first campaign was over, and there had scarcely been a collision between the troops of the two nations. Parthia had been insulted by a wanton attack, and had lost some disaffected cities; but no attempt had been made to fulfil the grand boasts with which the war had been undertaken.
It may be suspected that the Parthian monarch began now to despise his enemy. He would compare him with Lucullus and Pompey, and understand that a Roman army, like any other, was formidable, or the reverse, according as it was ably or feebly commanded. He would know that Crassus was a sexagenarian, and may have heard that he had never yet shown himself a captain or even a soldier. Perhaps he almost doubted whether the proconsul had any real intention of pressing the contest to a decision, and might not rather be expected, when he had enriched himself and his troops with Mesopotamian plunder, to withdraw his garrisons across the Euphrates. Crassus was at this time showing the worst side of his character in Syria, despoiling temples of their treasures, and accepting money in lieu of contingents of troops from the dynasts of Syria and Palestine. Orodes, under these circumstances, sent an embassy to him, which was well calculated to stir to action the most sluggish and poor-spirited of commanders. “If the war,” said his envoys, “was really waged by Rome, it must be fought out to the bitter end. But if, as they had good reason to believe, Crassus, against the wish of his country, had attacked Parthia and seized her territory for his own private gain, Arsaces would be moderate. He would have pity on the advanced years of the proconsul, and would give the Romans back those men of theirs, who were not so much keeping watch in Mesopotamia as having watch kept on them.” Crassus, stung with the taunt, exclaimed, “He would return the ambassadors an answer at Seleucia.” Wagises, the chief ambassador, prepared for some such exhibition of feeling, and, glad to heap taunt on taunt, replied, striking the palm of one hand with the fingers’ of the other: “Hairs will grow here, Crassus, before you see Seleucia.”
Still further to quicken the action of the Romans, before the winter was well over, the offensive was taken against their adherents in Mesopotamia. The towns which held Roman garrisons were attacked by the Parthians in force; and, though we do not hear of any being captured, all of them were menaced, and all suffered considerably.
If Crassus needed to be stimulated, these stimulants were effective; and he entered on his second campaign with a full determination to compel the Parthian monarch to an engagement, and, if possible, to dictate peace to him at his capital. He had not, however, in his second campaign, the same freedom with regard to his movements that he had enjoyed the year previous. The occupation of Western Mesopotamia cramped his choice. It had, in fact, compelled him before quitting Syria to decline, definitely and decidedly, the overtures of Artavasdes, who strongly urged on him to advance by way of Armenia, and promised him in that case an important addition to his forces. Crassus felt himself compelled to support his garrisons, and therefore to make Mesopotamia, and not Armenia, the basis of his operations, He crossed the Euphrates a second time at the same point as before, with an army composed of 35,000 heavy infantry, 4,000 light infantry, and 4,000 horse. There was still open to him a certain choice of routes. The one preferred by his chief officers was the line of the Euphrates, known as that which the Ten Thousand had pursued in an expedition that would have been successful but for the death of its commander. Along this line water would be plentiful; forage and other supplies might be counted on to a certain extent; and the advancing army, resting on the river, could not be surrounded. Another, but one that does not appear to have been suggested till too late, was that which Alexander had taken against Darius; the line along the foot of the Mons Masius, by Edessa, and Nisibis, to Nineveh. Here too waters and supplies would have been readily procurable, and by clinging to the skirts of the hills the Roman infantry would have set the Parthian cavalry at defiance. Between these two extreme courses to the right and to the left were numerous slightly divergent lines across the Mesopotamian plain, all shorter than either of the two above-mentioned, and none offering any great advantage over the remainder.
It is uncertain what choice the proconsul would have made, had the decision been left simply to his own judgment. Probably the Romans had a most dim and indistinct conception of the geographical character of the Mesopotamian region, and were ignorant of its great difficulties. They remained also, it must be remembered, up to this time, absolutely unacquainted with the Parthian tactics and accustomed as they were to triumph over every enemy against whom they fought, it would scarcely occur to them that in an open field they could suffer defeat. They were ready, like Alexander, to encounter any number of Asiatics, and only asked to be led against the foe as quickly as possible. When, therefore, Abgarus, the Osrhoene prince, soon after Crassus had crossed the Euphrates, rode into his camp, and declared that the Parthians did not intend to make a stand, but were quitting Mesopotamia and flying with their treasure to the remote regions of Hyrcania and Scythia, leaving only a rear guard under a couple of generals to cover the retreat, it is not surprising that the resolution was taken to give up the circuitous route of the Euphrates, and to march directly across Mesopotamia in the hope of crushing the covering detachment, and coming upon the flying multitude encumbered with baggage, which would furnish a rich spoil to the victors. In after times it was said that C. Cassius Longinus and some other officers were opposed to this movement, add foresaw its danger; but it must be questioned whether the whole army did not readily obey its leader’s order, and commence without any forebodings its march through Upper Mesopotamia. That region has not really the character which the apologists for Roman disaster in later times gave to it. It is a region of swelling hills, and somewhat dry gravelly plains. It possesses several streams and rivers, besides numerous springs. At intervals of a few miles it was studded with cities and villages; nor did the desert really begin until the Khabour was crossed. The army of Crassus had traversed it throughout its whole extent during the summer of the preceding year, and must have been well acquainted with both its advantages and drawbacks. But it is time that we should consider what preparations the Parthian monarch had made against the threatened attack. He had, as already stated, come to terms with his outlying vassals, the prince of Osrhoene, and the sheikh of the Scenite Arabs, and had engaged especially the services of the former against his assailant. He had further, on considering the various possibilities of the campaign, come to the conclusion that it would be best to divide his forces, and, while himself attacking Artavasdes in the mountain fastnesses of his own country, to commit the task of meeting and coping with the Romans to a general of approved talents. It was of the greatest importance to prevent the Armenians from effecting a junction with the Romans, and strengthening them in that arm in which they were especially deficient, the cavalry. Perhaps nothing short of an invasion of his country by the Parthian king in person would have prevented Artavasdes from detaching a portion of his troops to act in Mesopotamia. And no doubt it is also true that Orodes had great confidence in his general, whom he may even have felt to be a better commander than himself. Surenas, as we must call him, since his name has not been preserved to us, was in all respects a person of the highest consideration. He was the second man in the kingdom for birth, wealth, and reputation. In courage and ability he excelled all his countrymen; and he had the physical advantages of commanding height and great personal beauty. When he went to battle, he was accompanied by a train of a thousand camels, which carried his baggage; and the concubines in attendance on him required for their conveyance two hundred chariots. A thousand horseman clad in mail, and a still greater number of light-armed, formed his bodyguard. At the coronation of a Parthian monarch, it was his hereditary right to place the diadem on the brow of the new sovereign. When Orodes was driven into banishment it was he who brought him back to Parthia in triumph. When Seleucia revolted, it was he who at the assault first mounted the breach and, striking terror into the defenders, took the city. Though less than thirty years of age at the time when he was appointed commander, he was believed to possess, besides these various qualifications, consummate prudence and sagacity.
The force which Orodes committed to his brave and skillful lieutenant consisted entirely of horse. This was not the ordinary character of a Parthian army, which often comprised four or five times as many infantry as cavalry. It was, perhaps, rather fortunate accident than profound calculation that caused the sole employment against the Romans of this arm. The foot soldiers were needed for the rough warfare of the Armenian mountains; the horse would, it was known, act with fair effect in the comparatively open and level Mesopotamia. As the king wanted the footmen he took them, and left to his general the troops which were not required for his own operations.