Inside The Country

Iranian people inside the country since the time of Zoroaster (~1000 BC), or even before, have called the country Arya, Iran, Iranshahr, Iranzamin (Land of Iran), Aryānām (the equivalent of Iran in the protoIranian language) or its equivalents. The Pars tribe gave its name to where they lived (the modern-day province is called Fars/Pars a southern region) but the province in ancient times was smaller than its current area.

Outside of the country before March 1935 In the
Western world, Persia (or one of its cognates) was historically the common name for Iran until Persia was adopted from the Greeks who began to use adjectives such as Pérsēs (Πέρσης), Persikḗ (Περσική) or Persís (Περσίς) in the fifth century BC to refer to Cyrus (Korosh in Farsi) the Great’s empire (a word understood to mean “country”).

Alignment of internal and external name to IRAN
Nowruz (March) of 1935 Reza Shah Pahlavi (the then Monarch of Iran) based on recommendations from Saeed Nafisi, a revered Iranian scholar and writer, asked foreign delegates to use the term Iran, as the endonym (self-designated, homeland, or language) of the country, in formal correspondence, to align the country’s name internally and externally