They are related to the term "Aryan" and it is supposed that the plateau was occupied in prehistoric times by Indo-European peoples from Central Asia.
Through many invasions and changes of empire, this essential designation has remained a strong identifying marker for all populations living in this region and the many neighboring territories that fell under its influence due to conquest and expansion.
The term "Persian" is used as an adjective— especially pertaining to the arts—and to designate the principal language spoken in Iran.
The term is often used to designate the larger cultural sphere of Iranian civilization.
This is also true of some members of modern Iranian émigré populations in the United States, Europe, and elsewhere who do not wish to be identified with the current Islamic Republic of Iran, established in 1979. Iran is located in southwestern Asia, largely on a high plateau situated between the Caspian Sea to the north and the Persian Gulf and the Gulf of Oman to the south.
Its area is 636,300 square miles (1,648,000 square kilometers).
Other Turkic groups include the Qashqa'i tribe in the south and southwest part of the central plateau, and the Turkmen in the northeast.