Persian literature comprises oral compositions and written texts in the Persian language and is one of the world's oldest literatures. It spans over two-and-a-half millennia. Its sources have been within Greater Iran including present-day Iran, Iraq, Afghanistan, Pakistan, the Kurdistan Region, the Caucasus, and Turkey, regions of Central Asia (such as Tajikistan), South Asia and the Balkans where the Persian language has historically been either the native or official language.
For example, Rumi, one of the best-loved Persian poets, born in Balkh (in modern-day Afghanistan) or Wakhsh (in modern-day Tajikistan), wrote in Persian and lived in Konya (in modern-day Turkey), at that time the capital of the Seljuks in Anatolia. The Ghaznavids conquered large territories in Central and South Asia and adopted Persian as their court language. There is thus Persian literature from Iran, Mesopotamia, Azerbaijan, the wider Caucasus, Turkey, Pakistan, Bangladesh, India, Tajikistan and other parts of Central Asia, as well as the Balkans. Not all Persian literature is written in Persian, as some consider works written by ethnic Persians or Iranians in other languages, such as Greek and Arabic, to be included.