Vologases III of Parthia

Vologases III 𐭅𐭋𐭂𐭔
King of Kings
Coin of Vologases III, minted at Seleucia in 121/2
King of the Parthian Empire
Reign	110 – 147
Predecessor	Pacorus II (predecessor) Osroes I (rival king) Mithridates V (rival king)
Successor	Vologases IV
Died	147
Dynasty	Arsacid dynasty
Father	Pacorus II
Religion	Zoroastrianism

Vologases III (Parthian: 𐭅𐭋𐭂𐭔 Walagash) was king of the Parthian Empire from 110 to 147. He was the son and successor of Pacorus II (r. 78–110).

Vologases III's reign was marked by civil strife and warfare. At his ascension, he had to deal with the usurper Osroes I (r. 109–129), who managed to seize the western part of the empire, which left Vologases III in control of its eastern parts. After Osroes I violated the Treaty of Rhandeia with the Romans by appointing Parthamasiris as the king of Armenia in 113, the Roman emperor Trajan (r. 98–117) invaded the Parthian lands, briefly seizing the Parthian cities of Seleucia and Ctesiphon and reaching as far as the Persian Gulf. These gains were short-lived; all the Roman gains had been lost after Trajan's death in 117. Vologases III, whose eastern domains were untouched, took advantage of the weakened state of Osroes I to regain lost territory, and finally defeated him in 129. Another contender named Mithridates V shortly appeared afterwards, but was also defeated by Vologases III, in 140.

Vologases III had to face an invasion by the nomadic Alans from 134 to 136, while in the east, he sought to increase the political and military actions as a response to the enlargement of the Kushan Empire. Under the Roman emperor Antoninus Pius (r. 138–161), disturbance once occurred in Armenia due to the Romans appointing a new king in Armenia. Vologases III, however, did not protest, either due to not being powerful enough, or possibly because he did not want to put the thriving long-distance trade in jeopardy, from which the Parthian state was gaining hefty income from. Vologases III was succeeded by Mithridates V's son Vologases IV in 147.