The exhaustless showers of arrows which the garrison poured upon the Roman army, and the setting fire to the besieging machines by means of naphtha, initiated the Romans into the new dangers of Iranian warfare; and the brave commandant Mancaeus maintained the city, till at length the great royal army of relief had assembled from all parts of the vast empire and the adjoining countries that were open to Armenian recruiting officers, and had advanced through the north-eastern passes to the relief of the capital.
The leader Taxiles, experienced in the wars of Mithradates, advised Tigranes to avoid a battle, and to surround and starve out the small Roman army by means of his cavalry. But when the king saw the Roman general, who had determined to give battle without raising the siege, move out with not much more than 10,000 men against a force twenty times superior, and boldly cross the river which separated the two armies; when he surveyed on the one side this little band "too many for an embassy, too few for an army" and on the other side his own immense host, in which the peoples from the Black Sea and the Caspian met with those of the Mediterranean and of the Persian Gulf, in which the dreaded iron-clad lancers alone were more numerous than the whole army of Lucullus, and in which even infantry armed after the Roman fashion were not wanting; he resolved promptly to accept the battle desired by the enemy.
But while the Armenians were still forming their array, the quick eye of Lucullus perceived that they had neglected to occupy a height which commanded the whole position of their cavalry. He hastened to occupy it with two cohorts, while at the same time his weak cavalry by a flank attack diverted the attention of the enemy from this movement; and as soon as he had reached the height, he led his little band against the rear of the enemy's cavalry. They were totally broken and threw themselves on the not yet fully formed infantry, which fled without even striking a blow. The bulletin of the victor - that 100,000 Armenians and five Romans had fallen and that the king, throwing away his turban and diadem, had galloped off unrecognized with a few horsemen - is composed in the style of his master Sulla. Nevertheless the victory achieved on the 6th October 685 before Tigranocerta remains one of the most brilliant stars in the glorious history of Roman warfare; and it was not less momentous than brilliant.
All the Armenian Conquests Pass into the Hands of the Romans All the provinces wrested from the Parthians or Syrians to the south of the Tigris were by this means strategically lost to the Armenians, and passed, for the most part, without delay into the possession of the victor. The newly-built second capital itselfset the example. The Greeks, who had been forced in large numbers to settle there, rose against the garrison and opened to the Roman army the gates of the city, which was abandoned to the pillage of the soldiers. It had been created for the new great-kingdom, and, like this, was effaced by the victor. From Cilicia and Syria all the troops had already been withdrawn by the Armenian satrap Magadates to reinforce the relieving army before Tigranocerta. Lucullus advanced into Commagene, the most northern province of Syria, and stormed Samosata, the capital; he did not reach Syria proper, but envoys arrived from the dynasts and communities as far as the Red Sea - from Hellenes, Syrians, Jews, Arabs - to do homage to the Romans as their sovereigns. Even the prince of Corduene, the province situated to the east of Tigranocerta, submitted; while, on the other hand, Guras the brother of the great-king maintained himself in Nisibis, and thereby in Mesopotamia.
Lucullus came forward throughout as the protector of the Hellenic princes and municipalities: in Commagene he placed Antiochus, a prince of the Seleucid house, on the throne; he recognized Antiochus Asiaticus, who after the withdrawal of the Armenians had returned to Antioch, as king of Syria; he sent the forced settlers of Tigranocerta once more away to their homes. The immense stores and treasures of the great-king - the grain amounted to 30,000,000 medimni, the money in Tigranocerta alone to 8000 talents (nearly 2,000,000 pounds) - enabled Lucullus to defray the expenses of the war without making any demand on the state-treasury, and to bestow on each of his soldiers, besides the amplest maintenance, a present of 800 denarii (33 pounds).
The great-king was deeply humbled. He was of a feeble character, arrogant in prosperity, faint-hearted in adversity. Probably an agreement would have been come to between him and Lucullus - an agreement which there was every reason that the great-king should purchase by considerable sacrifices, and the Roman general should grant under tolerable conditions - had not the old Mithradates been in existence. The latter had taken no part in the conflicts around Tigranocerta. Liberated after twenty months' captivity about the middle of 684 in consequence of the variance that had occurred between the great-king and the Romans, he had been despatched with 10,000 Armenian cavalry to his former kingdom, to threaten the communications of the enemy. Recalled even before he could accomplish anything there, when the great-king summoned his whole force to relieve the capital which he had built, Mithradates was met on his arrival before Tigranocerta by the multitudes just fleeing from the field of battle. To every one, from the great-king down to the common soldier, all seemed lost. But if Tigranes should now make peace, not only would Mithradates lose the last chance of being reinstated in his kingdom, but his surrender would be beyond doubt the first condition of peace; and certainly Tigranes would not have acted otherwise towards him than Bocchus had formerly acted towards Jugurtha. The king accordingly staked his whole personal weight to prevent things from taking this turn, and to induce the Armenian court to continue the war, in which he had nothing to lose and everything to gain; and, fugitive and dethroned as was Mithradates, his influence at this court was not slight. He was still a stately and powerful man, who, although already upwards of sixty years old, vaulted on horseback in full armour, and in hand-to-hand conflict stood his ground like the best. Years and vicissitudes seemed to have steeled his spirit: while in earlier times he sent forth generals to lead his armies and took no direct part in war himself, we find him henceforth as an old man commanding in person and fighting in person on the field of battle. To one who, during his fifty years of rule, had witnessed so many unexampled changes of fortune, the cause of the great-king appeared by no means lost through the defeat of Tigranocerta; whereas the position of Lucullus was very difficult, and, if peace should not now take place and the war should be judiciously continued, even in a high degree precarious.