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.
Indo-European migrations
In Central Asia, the Turkic languages have marginalized Iranian languages as a result of the Turkic expansion of the early centuries CE. In Eastern Europe, Slavic and Germanic peoples assimilated and absorbed the native Iranian languages (Scythian and Sarmatian) of the region. Extant major Iranian languages are Persian, Pashto, Kurdish, and Balochi, besides numerous smaller ones.