He could scarcely prevent, and he does not seem to have tried to prevent, the recovery of Adiabene by the Parthians; but the nearer province of Gordyene to which they had an equal claim, he would by no means consent to their occupying.

At first he destined it for the younger Tigranes.

When the prince offended him, he made it over to Ariobarzanes, the Cappadocian monarch.

That arrangement not taking effect, and the tract being disputed between Phraates and the elder Tigranes, he sent his legate, Afranius, to drive the Parthians out of the country, and delivered it over into the hands of the Armenians.
At the same time he insulted the Parthian monarch by refusing him his generally recognized title of "King of Kings." He thus entirely alienated his late ally, who remonstrated against the injustice with which he was treated, and was only deterred from declaring war by the wholesome fear which he entertained of the Roman arms.
Pompey, on his side, no doubt took the question into consideration whether or no he should declare the Parthian prince a Roman enemy, and proceed to direct against him the available forces of the Empire.

He had purposely made him hostile, and compelled him to take steps which might have furnished a plausible _casus belli_.