The Persians, or Farsis, were originally the tribes that came to establish the Achaemenid Empire and now make up about 50% of the population.
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Commonly called ‘Turks’ in Iran, the Azaris make up about 25% of the population. They speak Azari Turkish, a dialect mixing Turkish with Farsi.
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Iran has more than six million Kurds. The Kurds lay claim to being the oldest Iranian people in the region, descended from the Medes. In Iran, Kurds live in the mountainous west, particularly Kordestan province near the Iraqi border. Kurds also live in Iraq, Syria and Turkey.
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Arabs make up about 3% of the Iranian population and are settled mostly in Khuzestan, near the Iraq border, and on the coast and islands of the Persian Gulf. They are often called bandari (bandar means port), because of their historical links to the sea. Their differing language (a dialect of Arabic), dress and faith (many are Sunni Muslims) mean other Iranians consider them exotic.
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..many of the more than 200,000 ethnic Iranians expelled from Iraq during the Iran–Iraq War have now settled permanently in Iran. Many were descended from Iranians who had settled in Iraq centuries before.