Literature in Iran
Persian is Iran's official language and the language of the country's ethnic majority (i.e., the Persians), and Persian literature has been the country's most influential literary tradition. Apart from Iran, Persian literature was used and developed further through several medieval Persianate societies in Asia Minor, Central Asia, and South Asia, and the language is still used widely in Central Asia (Tajikistan and Uzbekistan) and Afghanistan.
Zaza–Gorani languages
The area of the Northwestern Iranian languages was largely overrun by speakers of Turkic languages, subsequently known as Azeri or Azerbaijani, introduced in the 11th century. By the 16th century, this language had ousted the indigenous Iranian languages except from the peripheral area along the Caspian coast. Two of these northwestern dialects, however, survive outside the area; they are Zaza and Gorani. The Gorani moved south, but their language, now much declined, survives only in the neighbourhood of Kermanshah.