Iran is a diverse country consisting of people of many religions and ethnic backgrounds cemented by the Persian culture. Persians constitute the majority of the population.
Present-day Iranians, or Persians, are considered to be direct descendants of the Aryans who moved into the plateau in the second millennium BC. They speak Persian, or Farsi, and number more than half the total population. In the Zagros range and its extensions are to be found the Kurds, Lurs, Bakhtiari, Qashqai and Qajars; the first three are said to be of stock similar to the Iranian element, and they speak languages that stem from ancient Indo-European languages.
At various times after the 10th century AD, Turkish tribes settled in the region, and Turkish-speaking groups are still found in several parts of the country. One-eighth of the total population dwells in East and West Azerbaijan, and there are sizable groups of Azerbaijanis in major cities elsewhere, including Tehran. Arab groups arrived during and after the 7th century AD; their descendants live in the south and southwest and in scattered colonies elsewhere.
In general, non-Iranian elements are to be found along the perimeter of the country. Of these, certain nomadic groups move back and forth across the frontiers. Tribal groups have been a conspicuous element in Iran for many centuries, migrating vertically in spring and fall between high mountain valleys and hot, lowland plains. The important migratory groups include the Qashqai, Qajars, Bakhtiari, Baluchi and Turkmen. A large proportion of these people are now settled, however. The nomadic way of life is on the decline, and official policy has sought to resettle these groups on farmlands.
The main ethnic groups are Persians (51%), Azeris (24%), Gilaki and Mazandarani (8%), Kurds (7%), Arabs (3%), Baluchi (2%), Lurs (2%), Turkmens (2%), Laks, Qashqai, Armenians, Persian Jews, Georgians, Assyrians, Circassians, Tats, Mandaeans, Gypsies, Brahuis, Hazara, Kazakhs and others (1%).
Farsi, commonly called Persian in the West, is the official language of Iran. An Indo-European language of the Indo-Iranian group, Farsi derives from ancient Persian, with an admixture of many Arabic words. Arabic characters and script are used in writing modern Persian. Dialects of Turkish, or Turki – especially Azeri, the language of the Azerbaijanis – are spoken throughout northwestern Iran, by the Qashqai tribe in the southwest, and in parts of the northeast by Turkmen tribes and others. The Lurs, Kurds and Bakhtiari have languages and dialects of their own that descend from earlier Indo-European languages, and the Baluchi language spoken in southeastern Iran also is of Indo-European origin. A small number of Brahui in the southeast speak a Dravidian language.
Iran is the only Islamic country where Shi'a Muslims hold the reins of power. 89% of Iranians belong to the Twelver Shi'a branch of Islam, the official state religion, and about 9% belong to the Sunni branch, mainly Kurds and Iran's Baluchi Sunni. The remaining 2% are non-Muslim religious minorities, including Bahá'ís, Mandeans, Hindus, Sikhs, Yezidis, Yarsanis, Zoroastrians, Jews and Christians. The latter three minority religions are officially recognised and protected, and have reserved seats in the Majlis (Parliament). However the Bahá'í faith, Iran's largest religious minority, is not officially recognised, and has been persecuted during its existence in Iran. Since the 1979 revolution the persecution of Bahá'ís has increased with executions, the denial of civil rights and liberties, and the denial of access to higher education and employment.