Although only his books on the Roman Civil Wars survive in their entirety, large parts of other books have also come down to us. Fortunately, the Mithridatic Wars, about Rome's struggle with the kingdom of Pontus, belong to these better preserved parts. They are a very valuable source for the history of the Roman expansion in what is now called Turkey.
The translation was made by Horace White; notes by Jona Lendering.
Third Mithridatic War (cont'd)
 When Mancaeus beheld this defeat from Tigranocerta, he disarmed all of his Greek mercenaries because he suspected them.note[69 BCE.] They, in fear of arrest, walked abroad or rested only in a body, and with clubs in their hands. Mancaeus set upon them with his armed barbarians. They wound their clothing around their left arms, to serve as shields, and fought their assailants courageously, killed some, and shared their arms with each other. When they were sufficiently provided with weapons they seized some of the towers, called to the Romans outside, and admitted them when they came up. In this way was Tigranocerta taken, and the immense wealth, appertaining to a newly built and nobly peopled city, plundered.
 Nownote[68 BCE.] Tigranesnote[King Tigranes the Great of Armenia.] and Mithridates traversed the country collecting a new army, the command of which was committed to Mithridates, because Tigranes thought that his disasters must have taught him some lessons.
They also sent messengers to Parthia to solicit aid from that quarter. Lucullus sent opposing legates asking that the Parthians should either help him or remain neutral. Their kingnote[Phraates III.] made secret agreements with both, but was in no haste to help either of them.
Mithridates manufactured arms in every town. The soldiers he recruited were almost wholly Armenians. From these he selected the bravest to the number of about 70,000 foot and half that number of horse and dismissed the rest. He divided them into companies and cohorts as nearly as possible according to the Italian system, and turned them over to Pontic officers to be trained.
When Lucullus moved toward them,note[They had retreated to Artaxata, modern Yerevan, in the east of Armenia.] Mithridates, with all the foot-soldiers and a part of the horse, held his forces together on a hill. Tigranes, with the rest of the horse, attacked the Roman foragers and was beaten, for which reason the Romans foraged more freely afterward even in the vicinity of Mithridates himself, and encamped near him.
Again a great dust arose indicating the approach of Tigranes. The two kings had resolved to surround Lucullus. The latter perceived their movement and sent forward the best of his horse to engage Tigranes at as great a distance as possible, and prevent him from deploying from his line of march into order of battle. He also challenged Mithridates to fight. He began to surround him with a ditch, but could not draw him out. Finally, winter came on and interrupted the work on both sides.note[68/67 BCE. The winter quarters of Lucullus were in Nisibis.]
 Tigranes now withdrew into the interior of Armenia and Mithridates hastened to what was left of his own kingdom of Pontus, taking with him 4,000 of his own troops and as many more that he had received from Tigranes.note[67 BCE.] Lucullus slowly followed him, but was obliged to turn back frequently for want of provisions.
Mithridates made haste and attacked Fabius, who had been left in command by Lucullus, put him to flight, and killed 500 of his men. Fabius freed the slaves who had been in his camp and fought again an entire day, but the battle was going against him until Mithridates was struck by a stone on the knee and wounded by a dart under the eye, and was hastily carried out of the fight. For many days thereafter his forces were alarmed for his safety, and the Romans were quiet on account of the great number of wounds they had received.
Mithridates was cured by the Agari, a Scythian tribe, who make use of the poison of serpents as remedies. Some of this tribe always accompanied the king as physicians.
Triarius,note[Gaius Valerius Triarius.] the other general of Lucullus, now came with his own army to the assistance of Fabius and received from the latter his forces and authority. He and Mithridates not long afterward joined battle, during which a tempest of wind, the like of which had not been known in the memory of man, tore down the tents of both, swept away their beasts of burden, and even dashed some of their men over precipices. Both sides then retreated.
 News having been received that Lucullus was corning, Triarius hastened to anticipate his action and made a night attack upon the outposts of Mithridates. The fightnote[Near Zela.] continued for a long time doubtful, until the king made a powerful charge on that division of the enemy that was opposed to him and decided the battle. He broke through their ranks and drove their infantry into a muddy trench, where they were unable to stand and were slaughtered. He pursued their horse over the plain and made the most spirited use of the stroke of good luck until a certain Roman centurion, who was riding with him in the guise of an attendant, gave him a severe wound with a sword in the thigh, as he could not expect to pierce his back through his corselet. Those who were near immediately cut the centurion in pieces.
Mithridates was carried to the rear and his friends recalled the army, by a hasty signal, from their splendid victory. Confusion befell them by reason of the unexpectedness of the signal, and fear lest some disaster had happened elsewhere. When they learned what it was they gathered around the person of the king on the plain in consternation, until Timotheus, his physician, had stanched the blood and lifted the king up so that he could be seen. (In like manner in India, when Alexander was cured, he showed himself on a ship to the Macedonians, who were alarmed about him.)
As soon as Mithridates came to himself he reproved those who had recalled the army from the fight, and led his men again the same day against the camp of the Romans. But they had already fled from it in terror. In stripping the dead there were found 24 tribunes and 150 centurions. So great a number of officers had seldom fallen in any single Roman defeat.
 Mithridates withdrew into the country which the Romans now call Lesser Armenia, taking all the provisions he could and spoiling what he could not carry, so as to prevent Lucullus from getting any on his march. At this juncture a certain Roman of senatorial rank, named Attidius, a fugitive from justice, who had been with Mithridates a long time and had enjoyed his friendship, was detected in a conspiracy against him. The king condemned him to death, but not to torture, because he had once been a Roman senator. His fellow conspirators were subjected to dreadful tortures. The freedmen who were cognizant of the designs of Attidius he dismissed unharmed, because they were under obligations to their patron.
When Lucullus was already encamped near Mithridates, the proconsul of Asia sent heralds to proclaim that Rome had accused Lucullus of unnecessarily prolonging the war, and had ordered that the soldiers under him be dismissed, and that the property of those who did not obey this order should be confiscated. When this information was received the army disbanded at once, all but a few, who remained with Lucullus because they were very poor and did not fear the penalty.