Arsaces’ historic invasion of Parthia was a process.
Before Arsaces I, King and founder of the Arsacid dynasty, and his brother, Tiridates captured Parthia, they appeared to be residing in the province previous to the appointment of Andragoras as satrap, or governor. Andragoras gained this position due to Arsaces and Tiridates killing the last two previous satraps by the names of Pherekles and Agathokles.

