WORLD RELIGIONS

Detailed explanation-1: -Ancient Iran, historically known as Persia, was the dominant nation of western Asia for over twelve centuries, with three successive native dynasties-the Achaemenid, the Parthian, and the Sasanian-controlling an empire of unprecedented size and complexity.

Detailed explanation-2: -Islamic Republic of Iran. (Persian)

Detailed explanation-3: -Because “Persian” relates to ethnicity while “Iranian” encompasses a nationality. You can be Iranian and not necessarily be Persian. You can be Iranian and be Mazandarani, Gilaki, Kurdish, Lur, Baloch, Azeri, Turkmen, Arab or another ethnicity. You can be Iranian and not speak Persian.