At the same time she had been witness of the tremendous struggle between Rome and Pontus which commenced in B.C.88, was still continuing, and still far from decided, when Sanatroeces came to the throne.

An octogenarian monarch was unfit to engage in strife, and if Sanatroeces, notwithstanding this drawback, had been ambitious of military distinction, it would have been difficult for him to determine into which scale the interests of his country required that he should cast the weight of his sword.

On the one hand, Parthia had evidently much to fear from the military force and the covetous disposition of Tigranes, king of Armenia, the son-in-law of Mithridates, and at this time his chosen alley.

Tigranes had hitherto been continually increasing in strength.

By the defeat of Artanes, king of Sophene, or Armenia Minor, he had made himself master of Armenia in its widest extent; by his wars with Parthia herself he had acquired Gordyene, or Northern Mesopotamia, and Adiabene, or the entire rich tract east of the middle Tigris (including Assyria Proper and Arbelitis), as far, at any rate, as the course of the lower Zab; by means which are not stated he had brought under subjection the king of the important country of Media Artropatene, independent since the time of Alexander.
Invited into Syria, about B.C.83, by the wretched inhabitants, wearied with the perpetual civil wars between the princes of the house of the Seleucidae, he had found no difficulty in establishing himself as king over Cilicia, Syria, and most of Phoenicia.