Tiridates I of Parthia

Tiridates or Teridates or Tirdad or تیرداد /tᵻˈrɪdətiːz/ is a Persian name, given by Arrian in his Parthica to the brother of Arsaces I, the founder of the Parthian kingdom, whom he is said to have succeeded in about 246 BC. But Arrian’s account seems to be quite unhistorical and modern historians believe that Arsaces continued to rule Parthia until 211 BC.

In Arrian's account, Tiridates maintained himself for a short time in Parthia, during the dissolution of the Seleucid empire by the attacks of Ptolemy III in 246 BC and the following years. Tiridates was defeated and expelled by Seleucus II in about 238 BC. But when Seleucus was forced, by the rebellion of his brother, Antiochus Hierax, to return to the west, Tiridates came back and defeated the Macedonians. Tiridates adopted the name of his brother Arsaces, and after him all the other Parthian kings.

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