Hellenes in Iran

Hi everybody!I'm starting a new 1.1 Arche campaign.This time around I'd like to extensively roleplay the leading characters as well as the entire historical situation.I'm thinking that I should withdraw my forces to those iranian provinces most influenced by the hellenistic paradigm.So,which of the iranian provinces actually sustained considerable hellenic/hellenistic populations?When did the last signs of hellenistic influence died out in the iranian plateau?Were there any hellenic speaking populations settled in the polis of Media,Persis etc?I know I have a lot of questions...Any input would be greatly appreciated!Thanks in advance.

My knowledge is very limited, but from what I've read there was a rather large colony of Thraikians either in Persepolis or in a city nearby. Anyone else have more knowledge?

you can look up the EB Library, write it to thread seach.
It has many good reference books.