Hitherto no occasion had arisen for any direct dealings between Rome and Parthia. Their respective territories were still separated by considerable tracts, which were in the occupation of the Syrians, the Cappadocians, and the Armenians. Their interests had neither clashed, nor as yet sufficiently united them to give rise to any diplomatic intercourse. But the progress of the two Empires in opposite directions was continually bringing them nearer to each other; and events had now reached a point at which the Empires began to have (or seem to have) such a community of interests as led naturally to an exchange of communications. A great power had been recently developed in these parts. In the rapid way so common in the East. Mithridates V., of Pontus, the son and successor of Rome’s ally, had, between B.C. 112 and B.C. 93, built up an Empire of vast extent, numerous population, and almost inexhaustible resources. He had established his authority over Armenia Minor, Colchis, the entire east coast of the Black Sea, the Chersonesus Taurica, or kingdom of the Bosporus, and even over the whole tract lying west of the Chersonese as far as the mouth of the Tyras, or Dniester. Nor had these gains contented him. He had obtained half of Paphlagonia by an iniquitous compact with Nicomedes, King of Bithynia; he had occupied Galatia; and he was engaged in attempts to bring Cappadocia under his influence. In this last-named project he was assisted by the Armenians, with whose king, Tigranes, he had (about B.C. 96) formed a close alliance, at the same time giving him his daughter, Cleopatra, in marriage. Rome, though she had not yet determined on war with Mithridates, was resolved to thwart his Cappadocian projects, and in B.C. 92 sent Sulla into Asia with orders to put down the puppet whom Mithridates and Tigranes were establishing, and to replace upon the Cappadocian throne a certain Ariobarzanes, whom they had driven from his kingdom. In the execution of this commission, Sulla was brought into hostile collision with the Armenians, whom he defeated with great slaughter, and drove from Cappadocia together with their puppet king. Thus, not only did the growing power of Mithridates of Pontus, by inspiring Rome and Parthia with a common fear, tend to draw them together, but the course of events had actually given them a common enemy in Tigranes of Armenia, who was equally obnoxious to both.