The route to great acquisitions in the west seemed to open before Phraates, if the nomads did not stop him. Weakened in his struggle against Antiochus VII, he called on the Śaka nomads to the north of his frontiers for aid, promising them payment. The reinforcements arrived too late to be of use; he sent them back, which provoked them to revolt and pillage the countryside. The Greek prisoners drafted by Phraates into his army participated in the pillaging, and Phraates lost his life fighting them. The same fate was reserved for his successor and uncle, Artabanus II (c. 128–124/123 bc). The Śaka were pushed back with some difficulty toward Drangiana, to which they gave their name, Sakastan (Sīstān). Another branch of the vast nomadic movement crossed the Oxus and put an end to the Greco-Bactrian kingdom, on the ruins of which the powerful Kushān kingdom was to be built.
The second stage of the phil-Hellenistic period extends from the first quarter of the 2nd century until about 30 bc and embraces a period when Parthia reached the apogee of its power and worldwide territorial expansion. Mithradates II
The reign of Mithradates II, from 123 to 88 bc, constitutes the most glorious chapter of Parthian history. It put an end to the ambitions of Artabanus’s son Himerus, left by his father as governor of Mesopotamia, and brought Hyspaosines, king of Mesene (Characene), who had extended his possessions too far toward the north, back into submission. In the east the Śaka were on the move—soon an independent state would be formed there that would push toward eastern Iran and India; in the 1st century bc two dynasties, the Indo-Scythian and the Indo-Parthian, whose members would remain closely linked to the Arsacid dynasty, were to reign in that region. They would disappear after being absorbed by the Kushān kingdom.
The eastern frontiers of Mithradates II incorporated Margiana and Aria. Once order was restored in the east, the king turned toward the west: he placed Tigranes II (the Great) on the throne of Armenia, and, extending his hegemony over this kingdom and over eastern Asia Minor, he organized pressure on the last Seleucids. A meeting with Rome, which had already formed a “Province of Asia” in Asia Minor, became inevitable and took place in 92 bc on the Euphrates River between the Roman general Lucius Cornelius Sulla and the Parthian ambassador Orobaze. Mithradates II wisely refused to agree to follow in the Roman path and preferred to retain his neutrality in the struggle between Rome and Mithradates VI Eupator of Pontus. Rome in the west and Parthia in the east met as Alexander’s successors and, with a common accord, settled the inheritance. The two parties recognized the Euphrates as a common frontier. It seems there was no longer a question of either an alliance or a signed convention. Upon his return, Orobaze paid with his head for the lèse-majesté he had committed by accepting a seat lower than Sulla’s at their meeting.
For the first time, Parthian power entered into direct contact with the Chinese empire and received an embassy from the Han emperor Wudi (140–87 bc), who dispatched an escort of 20,000 men to meet the Parthians. The Chinese were particularly interested in the horses raised in Fergana, which they needed to create a cavalry to fight the nomadic Xiongnu on their northern border.
At the zenith of his power, Mithradates II took the title of “king of kings”; in the east as well as in the west, his empire achieved a position of power and stability previously unknown. He maintained diplomatic relations with the two greatest world powers, Rome and China. Mithradates I, Phraates II, and Mithradates II were the true creators of the Parthian state, winning for it military and economic victories and raising it to a level comparable to that of the Achaemenian Empire. After the death of Mithradates II, a short period of intrigue and rivalry saw the succession, in turn, of Gotarzes I, Orodes I, and Sanatruces. The latter came to power late in life and was replaced in 70 bc by his son, Phraates III (70–58/57 bc), under whom sustained contacts with Rome took place. Wars with Rome
In 69 bc the Roman general Lucius Licinius Lucullus, in charge of looking after Roman interests in the East, attempted to lure Phraates III into an alliance that would help Rome in its struggle against Pontus and Armenia, but the Parthian king, while still maintaining “friendly” relations with Rome, retained his neutrality. An agreement with the Romans renewed the Euphrates line as a frontier. Three years later the Roman general Pompey the Great replaced Lucullus and succeeded in concluding a real alliance with Phraates III. This proved, however, to be of short duration, for affairs in Armenia, aggravated by Roman operations on Parthian territory, had brought the two empires to a parting of the ways. Pompey replied to Phraates’ protestations by occupying Gordyene, a vassal state of the Parthians, and addressed Phraates with the simple title “king.” Pompey did not trouble himself over entering into direct relations with the sovereigns of Media and Elymais, vassals of Phraates. The position taken by the Romans toward the king of kings was rather more like that of conquerors than of allies. Pompey’s policy became clear: from the Caucasus to the Persian Gulf, he hoped to create a wall of states friendly to Rome that would encircle Parthia, in preparation for Roman conquest.
That action fell within the jurisdiction of the Roman triumvir Marcus Licinius Crassus. As early as 57 bc a conflict with Rome broke out over the case of Mithradates III (58/57–55 bc), who, opposing Orodes II (c. 57–37/36 bc), his brother (both having killed their father, Phraates III), fled to Syria and asked the legate Aulus Gabinius for aid and asylum. The Roman Senate forbade Gabinius to involve himself in the dispute over the succession to the Parthian throne. Three years later the tension between the two powers was settled in bloody fashion, and the rupture was consummated in 53 bc. Without provocation, the army of Crassus—the only one of the triumvirs without military glory (Julius Caesar was conqueror of Gaul, and Pompey was conqueror of the Middle East)—crossed the Euphrates. Orodes protested and invoked the treaty of friendship in vain. Crassus refused to reply until he arrived at Seleucia on the Tigris. It was a brutal breaking of all the agreements concluded in 69 and 66 bc.
The Battle of Carrhae (53 bc), with the Parthians led by Surenas with his light and heavy cavalry, cost Rome seven legions and the lives of Crassus and his son. Through Surenas’s brilliant victory the routes to Iran and India were closed to Rome, and its ambitions in the Orient were so weakened that the Euphrates became not only a political but also a spiritual frontier; no effort at Romanization beyond it was possible any longer. A united Greco-Iranian front protected Asia against the Romanization of Iranianized Hellenism and destroyed the myth of Roman invincibility.
The insignia of the Roman legions fell into Parthian hands, and 10,000 Roman prisoners were sent into captivity in Margiana. The victory over Crassus had great repercussions among the peoples of the East. It shook the Roman position in Asia Minor, Syria, and Palestine, while it restored the Parthians’ confidence in their power and in their ability to resist Rome and promised them a dominant position among the peoples of the East. According to the Greek writer Plutarch, the severed head of Crassus was brought to Orodes like a hunting trophy while he was attending a presentation of Euripides’ play The Bacchae.