Hecatompylos Iran

…Parthia.

After crushing a third revolt in Susiana, Darius has by now slain nine rebel leaders in nineteen battles.

Darius now moves against the rebellious satraps, consolidating and further extending Persian conquests.

…he founds such cities as Nisa, where he will be buried.

These new cities are usually named after the king or the dynasty.

Arsaces seems not to have infringed upon the rights of the Greeks and Macedonians living in these cities, perhaps hoping to win their support.

From the beginning, while maintaining the autonomy of the cities, he makes use of propaganda to ensure their continuing obedience.

He installs his capital at Hecatompylos (southeast of the Caspian Sea), on the Silk Road in western Khurasan.

(Although it is thought to have been built at a location now between the Iranian cities, Damghan and Shahrud, its precise site has not been established.)

The Arsacids begin to recover many of the dominions of the Persian empire, organizing the Parthian realm into several small states.

A feudal nobility, which acknowledges the authority of the Arsacid dynasty but enjoys a considerable degree of independence, controls these polities.

Parthian activity had forced Demetrius II to take action in 139 BCE.

Marching against Mithridates I, king of Parthia, he was initially successful, but is defeated in the Iranian mountains and taken prisoner the following year.

This effectively ends Seleucid claims to any land east of the Euphrates river.

The Babylonian province of the Seleucid empire becomes Parthian, but …

Parthian ruler Mithridates I had died in 138 BCE; his son and successor rules as Phraates II.

The Parthians, perhaps hopeful of stirring up civil war behind Antiochus, release his brother Demetrius, who has been their prisoner for a decade.

The Yuezhi are apparently involved in a war against the Parthians in 124 BCE, during which the Parthian king Artabanus I of Parthia is wounded in the arm and dies immediately; his successor is Mithridates II.

Orobaze pays with his head upon his return to Hecatompylos for the lèse majesté he had committed by accepting a seat lower than Sulla's at their meeting.

The legitimate successors of Pacorus II: Osroes I (105–116 and 117–129), Parthamaspates (116–117), and Mithridates IV (129–140), who ruled Mesopotamia, had been preoccupied by conflicts with the Romans, particularly the invasion by Roman emperor Trajan (98–117), and thus were unable to effectively challenge Vologases III.

Following the death of Osroes I, Vologases III had extended his rule through most of Parthia but had to contend with Mithridates IV, incursions of the nomadic Alans into Cappadocia, Armenia, and Media, and rebellion in Iran by an unknown usurper around 140.

The Parthian realm is finally reunited after Vologases III's death in 147 by Vologases IV (147–191), the son of his rival Mithridates IV.

Vologases III's Armenian kingship had been given to Sohaemus in 144, for unknown reasons.