Vologases I of Parthia

Vologases I of Parthia (Persian: ولاش يکم‎), sometimes called Vologaeses or Vologeses or, following Zoroastrian usage, Valakhsh (Persian: بلاش‎ Balāsh) ruled the Parthian Empire from about 51 to 78. Son of Vonones II by a Thracian concubine, he succeeded his father in 51 AD. He gave the kingdom of Media Atropatene to his brother Pacorus II, and occupied Armenia for another brother, Tiridates. This led to a long war with the Roman Empire (54–63), which was ably conducted by the Roman general Corbulo.

The power of Vologases was weakened by an attack of the Dahae and Sacae nomads, a rebellion of the Hyrcanians, and the usurpation of his son Vardanes II. According to Josephus, he was prevented from attacking the vassal king of Adiabene by an invasion of the eastern nomads. At last, a peace was concluded, by which Tiridates was acknowledged as king of Armenia, but had to become a vassal of the Romans; he went to Rome, where Roman emperor Nero gave him back the diadem; from that time an Arsacid dynasty ruled in Armenia under Roman supremacy.

Vologases was satisfied with this result, and honored the memory of Nero (Suetonius Nero, 57), though he stood in good relations with Vespasian also, to whom he offered an army of 40,000 archers in the war against Vitellius. Soon afterwards the Alans, a great nomadic tribe beyond the Caucasus, invaded Media and Armenia; Vologases applied in vain for help to Vespasian. It appears that the Persian losses in the east also could not be repaired; Hyrcania remained an independent kingdom. Vologases died in about 78 and was succeeded by his son Vologases II.

Read more about Vologases I Of Parthia:  Vologases and The Iranian Revival