Helios

I am intrigued by how these changing of name took place. Why would a country like Persia with such rich history and long existence change name to Iran, do they not want to be associated with Persia history?
Same question about Siam and Thailand.

hazratemahmood

The name "Iran" was possibly in use from 3000 years ago, when all Aryan tribes still lived in Central Asia and called their land "Ayrianem Vaeja" as attested in old Avestan texts.

The problem here is that westerners usually overlook something important: Greeks made contact with Persians in 500 BC, when the nation was still under development and was under the control of the Persian tribes. During the Sassanid era (200 - 600 AD), the country was fully developed and collectively called Eran/Eranshahr (The state/land of Aryans), yet the Romans who came into contact with Greeks adopted the old name Persis for this country, which was actually the name of a region in Iran called Pars (Fars province today).

So for Iranians themselves, the nation had always been called Iran and never Pars, because those people were simply not just "Persians" but a large number of them were descendants of other Aryan tribes.