Mithridates had little hope of withstanding Pompey, when he had barely been able to hold his own against Lucullus. However, he encamped in a strong position on a hill, and hoped that this would make an attack difficult, perhaps even impossible.
Pompey, leaving his fleet to guard the seas, marched into Pontus, but not before the king had been driven from the hill on which he had entrenched himself, by lack of water for his army.
The Roman general had more discerning eyes than the old king. For he, noticing that the plants were green and healthy, encamped on this same hill, and when his soldiers complained of thirst he bade them dig wells. As he expected, there was soon abundance of water in the camp.
But Pompey did not linger long on the hill, for he was eager to follow Mithridates, and soon after this the king found his camp besieged so closely by the Romans that it was impossible to get supplies for his army. It was plain that he and his soldiers must either starve or escape.
So one night Mithridates ordered the sick and wounded to be killed, for they would have hampered the army in its flight. The king did not hesitate to give such a cruel order, for he and his followers had not been taught to pity the weak and helpless.
The watch-fires were lighted at the usual time, that the suspicions of the Romans might not be roused. Then when the camp seemed quiet for the night, Mithridates and the main body of the army slipped out into the dark, and somehow succeeded in passing unnoticed through the Roman lines.
In dread of pursuit, they hid themselves by day in forests, at night they marched as quickly as possible toward the river Euphrates.
When Pompey found that Mithridates had escaped, he blamed his own carelessness and followed swiftly in pursuit. As he marched by day as well as by night, he was soon in advance of the king. So it happened that when Mithridates encamped by the banks of the river Euphrates, the Romans were already there, and determined that the enemy should not again escape.
But the very first evening as it grew dark Pompey became restless. He had set a strict watch, it was true, yet Mithridates had already shown himself skilful in evading sentinels. It would be safer to attack the camp without delay. Pompey summoned his officers, and arranged that the assault should take place at midnight.
Meanwhile, Mithridates lay asleep in his tent, worn out with fatigue and anxiety. As he slept, his troubles slipped from his mind, and the old king dreamed pleasant dreams. He thought that he had reached the sea, and was in a ship. The winds blew soft and fair, wafting the vessel quietly along toward a harbour where no foes could touch him.