In any case, Arabic is not and has never been Iran’s official language. Majority of Iranians have been speaking Persian for thousands of years. Iranian Arabs along with other ethnic groups (like Azeris, Armenians and etc.) usually speak their mother tongues as well.

The official language of Iran is Persian and it is the mothertongue of ~63% of the population. Azerbaijani is the second most spoken language, then followed by Kurdish, Lurish and Baluchi. A lot of areas in the country are linguistically mixed due to the fact that

The official language of Iran (Persia) and Tajikistan as well as one of the two main official languages of Afghanistan is called Persian in the English language. Farsi, on the other hand, is the name of the same language in Persian. The same way that English is called Engelisi in Persian but English in English.

Tajikistan: Persian (Tajiki) is the only official language and is spoken by the majority of the population. Iran: Persian (Farsi) is the only official language and spoken by the majority of the population, and non-Persian minorities speak it as their first or second language.

By “official language” I imagine that you mean “basic language of imperial administration” in Achaemenid Iran. Yes, you are correct: in the Achaemenid Empire (sixth to fourth centuries B.C.) the basic language of imperial administration was indeed a Semitic language, namely Aramaic ( pace Brian Collins, whose answer contains only correct information, just not the information …

Iranians speak Persian, which is the official language of Iran. Persian is the native language of about 60% of the Iranian population who identify as ethnically Persian. It is the second language of the remaining ...