Alexander entered Persis, the cradle of the Achaemenian house, and came upon fresh masses of treasure in the royal city, Persepolis.
It was inhabited by an Iranian tribe, the Parthava of the inscriptions of Darius; the correct Greek form is HapOvaioc. Parthia became a province of the Achaemenian and then of the Macedonian Empire.
In Cappadocia two Persian houses, relics of the old aristocracy of Achaemenian days had carved out principalities, one of which became the kingdom of Pontus and the other the kingdom of Cappadocia (in the narrower sense); the former regarding Mithradates (281-266) as its founder, the latter being the creation of the second Ariarathes (?302-?281).
It was borne by three kings of the Achaemenian dynasty of ancient Persia; though, so long as its meaning was understood, it can have been adopted by the kings only after their accession to the throne.
By the Achaemenian period Aramaic had become the international language, and was adopted officially.