De-Iranianization is the process of removing the Persian identity of Iran. It started in earnest after the Islamic conquest of Persia. It got a re-invigorating jolt with the re-introduction of Islamic laws in 1979 after the Islamic Revolution.
According to one journalist who spent several years in Iran, "The Islamic system of government has deliberately erased much of what was Persian culture and it is only by looking hard that you can catch glimpses of the past."
Since the establishment of Islamic Republic, fundamentalists have initiated the policy of de-Iranianization of the Iran, by replacing the notion of Iranian Identity and Nationality with Islamic Identity, both inside and outside Iran. Imam Khomeini has emphasized this goal in several of his speeches, for example, on Dec 1980 (as published in Kayhan):
- "Those who say that we want nationality, they are standing against Islam....We have no use for the nationalists. Moslems are useful for us. Islam is against nationality...."
- "These issues that exist among people that we are Iranian and what we need to do for Iran are not correct; these issues are not correct. This issue, which is perhaps being discussed everywhere, regarding paying attention to nation and nationality is nonsense in Islam and is against Islam. One of the things that the designers of Imperialism and their agents have promoted is the idea of nation and nationality."
Mehdi Bazargan, the first Prime minister of Islamic Republic, once said: "Imam [Khomeini] wants Iran for Islam and we want Islam for Iran." Due to the commitment to Pan-Islamism inherent in Iranian Islamic revolutionary ideology, the Islamic Republic's attitude toward Sunni Islam is positive.
In the outset of the Islamic Revolution, one of the most-notorious clerics in Iran, Sadeq Khalkhali known as the hanging judge, who was renowned for his brutality and mass executions in post-revolutionary Iran, tried to destroy 2500-year-old Persepolis, and after that the mausoleum of Ferdowsi. He was stopped by the efforts of the locals.
Defaming Cyrus the Great, Islamic fundlamentalist Ayatollah Sadeq Khalkhali wrote an article entitled "Kourosh-e Doroughin" (Impostor Cyrus) shortly after the revolution. In 2001, Nasser Pourpirar wrote two books entitled "Twelve centuries of silence" and "A bridge to past", claiming that the Sassanid empire and Parthian Empires never existed, and are the fabrications of Jewish and American orientalists.
The Arabic language has been held in high esteem by the Islamic Republic from the beginning. Since early days of the Islamic Revolution, there has been an Arabic resurgence by the Islamic Regime in Iran. Most of the prominent members of the Islamic regime and clerics have caused a considerable number of new Arabic entering Persian. Ayatollah Khomeini, the founder of the regime, made no secret of his contempt for Iranian culture and values, including the Persian language. From the early days of the revolution, he injected Persian with so many Arabic words that it confounded the ordinary listener, something for which he compensated by repetitiveness. But as popular as he was in those early days of the revolution, the public's backlash against his stance on pre-Islamic Iranian heritage. Since then, the most detailed and explicit statement about Arabic was made by Ayatollah Hashemi Rafsanjani in 1981 in an important Sermon linking the fate of Persian language directly to that of Persian nationality: "both shall vanish as soon as Islamic unity is attained".
Apart from high-ranking authorities of the regime, many minor agents of the Islamic Republic used any opportunities to attack Persian language and replace it with Arabic. According to one of these muslim extremists, Poorpirar: "It is very unfortunate that we can not put the Persian language aside and replace it with the language of Koran. However the future of Iran is at the hand of Islamic Unity. Spreading Arabic language among Iranian youths and incorporating it more seriously into the education system [...] can make a foundation for such Islamic Unity." As an Islamic fundamentalist and a neoconservative political analyst who is infamous for his anti-Semitic, anti-Iranian and anti-Western rhetorical slogans, Pourpirar has praised Saddam Hussein and refered to him as the "Great Arab hero" and the "symbol of resistance."According to some sources, Pourpirar is of Arab origin, whose parents were [raqi-Libiyan refugees who migrated to Iran.  In his earlier life, Pourpirar was closely involved with the Iranian Communist Party, which had close relations with the Communist Party of the Soviet Union. After the Islamic Revolution, he joined with the revolutionaries. According to Alireza Nurizadeh, a renowned Iranian journalist based in the UK, Naser Pourpirar was an interrogator with the Islamic Revolutionary Courts before proclaiming himself as a scholar and historian. 
The tradition of banning names dates to the beginning of the Islamic Revolution in the early 1980s, when Iran's conservative leaders sought to purge the country of both Western culture and its own Persian, pre-Islamic past. Fundamentalists consider it unfortunate that Iranians used to be Zoroastrians, or that the ancient Persian empire achieved its greatest triumphs before Islam's arrival. To that end, they compiled a long list of forbidden names that included Zoroastrians gods and goddesses, commanders of ancient Persian armies, and other such tainted, best-forgotten figures. Indeed, Arabic names, except for a handful of Sunni villains, were fine. Persian ones, despite originating from the language actually spoken in Iran, had to be checked against the official list. Along the way, other politically inconvenient realities were fought on the baby name terrain. Wishing to quell an uprising by ethnically Kurdish Iranians in the north, the government banned Kurdish names.  Street names had changed from old Persian names to Arabic and Muslim names .This whole shift of the Iranian identity toward a more Islamic one created a kind of crisis.
Iranian society on the other hand, identify itself as Iranian. In Iran-Iraq war for example, all Iranians irrespective of their religions and ethnic groups defended the country. Also in occasions where a conflict between nationality and religion occurs, Iranian will not put their nationality aside. For instance when Norouz and Ashura conincide, Shia Iranians celebrate the ancient Iranian celebration with other Iranians. Abdolkarim Soroush, foremost Iranian religious intellectual, once suggested to adapt the religion to Iranian culture by organizing Ashura and other Islamic festivals according to Iranian calendar instead of Islamic calendar to avoid conflicts between Iranian identity and religion. 
As the result of Islamic Regime's "de-Iranianization policy", the Iranian patriotism to the point of chauvinism has been on the rise. Pre-Islamic holidays are being celebrated with unprecedented fanfare. The Persian lexicon has turned into a bastion of nationalism. Numerous Persian synonyms have been invented (originated from the Old and the middle-Persian Pahlavi) to replace the most commonly used foreign words, primarily Arabic/Islamic ones; -To everyone's wonder, the new words have caught on.
Following an order by Grand Ayatollah Ali Khamenei the fire festival has been banned by the regime since it is of Zoroastrian origins and is not Islamic. However, due to internal opposition, the government had to step back.
- Frances Harrison,"Farewell to a changed, subtle Iran", BBC News, 7 July 2007
- Amil Imani. The Mullahs Ruling Iran Are Not Iranians (English) (PDF). www.kavehroom.com. Retrieved on 2007-07-01.
- [Mehregan Magazine, Volume 12, Numbers 1 & 2, Spring & Summer 2003, p 16.]
- [Mehregan Magazine, Volume 12, Numbers 1 & 2, Spring & Summer 2003, p 16.]
-  Ayatollah Sadeq Khalkhali, The Guardian Unlimited, dated December 01, 2003; accessed January 11, 2007
- *Islam, Culture, Arts, History, Sufism, and ...*
-  New Persian, CAIS Online; accessed January 11, 2007
-  Power Grids Threaten World Registration of Ferdowsi Mausoleum, CAIS Archaeological and Cultural News - December 25, 2006; accessed January 11, 2007
-  Power Grids Threaten World Registration of Ferdowsi Mausoleum CAIS Archaeologicla and Cultural News; CAIS Online, accessed January 11, 2007
- MICHAEL SLACKMAN,"Ayatollahs Aside, Iranians Jump for Joy at Spring", New York Times, March 20, 2006