|"Great King" (Basileus Megas)'|
|Usurper King of the Seleucid Empire |
(King of Syria)
|Successor||King Demetrius I Soter|
Timarchus or Timarch was a usurper in the Seleucid empire between 163–160 BC.
A Greek nobleman, possibly from Miletus in Asia Minor, Timarchus was a friend of the Seleucid prince Antiochus IV Epiphanes during his time as a hostage to the Roman Republic. He was appointed satrap of Media in western Iran when Antiochus IV Epiphanes became king in 175 BC, and his brother Heracleides became minister of the royal finances. The Persian part of the empire was threatened by the Parthian kingdom, and Timarchus probably spent much of his time reinforcing the defences. The Seleucid realms probably extended as far as the area of Teheran during this time.
In the turmoil following the death of Antiochus IV during a Persian campaign in 164 BC, Timarchus became the more or less independent ruler of Media, opposing the general Lysias who acted as steward for the infant king Antiochus V Eupator, son of Antiochus IV.
In 162 BC Demetrius I, the proper heir to the Seleucid throne, became king, killing Lysias as well as the young Antiochus V. This may well have been the provocation that caused Timarchus to take the final step to independence and declare himself king.
Timarchus now managed to extend his realm into Babylonia, where records of his reign were inscribed into the astronomical calendars. His forces were however not enough for the legal Seleucid king: Demetrius defeated and killed Timarchus in 160 BC, and the Seleucid empire was temporarily united again.
Timarchus was one of the last Hellenistic kings in Iran but unfortunately little is known of his reign, except the short - and stereotypical - notion by Appian that Timarchus was a tyrant. On his coins, he introduced the epithet "Great King" (Basileus Megas) which was the traditional Achaemenid title and may reflect an effort to gather support from the natives in a time when the Seleucid empire lost ground in Iran. He was inspired by the Bactrian king Eucratides the Great, who had taken the same assuming title a few years earlier.
Timarchus was survived and avenged by his brother Heracleides, who eventually became champion of Alexander Balas, a boy that he claimed was a natural son of Antiochus IV. Heracleides convinced the Roman Senate to support the young pretender against Demetrius, who was defeated and killed in 150 BC. Thus the family of Timarchus contributed in no little way to the disintegration of the Seleucid empire.