Persian literature spans over two-and-a-half millennia. Its sources have been within Greater Iran including present-day Iran, Iraq, Afghanistan, the Caucasus, and Turkey, regions of Central Asia (such as Tajikistan) and South Asia where the Persian language has historically been either the native or official language. 

For instance, Rumi, one of best-loved Persian poets born in Balkh (in what is now the modern-day Afghanistan) or Vakhsh (in what is now the modern-day Tajikistan), wrote in Persian and lived in Konya (in what is now the modern-day Turkey), then the capital of the Seljuks in Anatolia. The Ghaznavids conquered large territories in Central and South Asia and adopted Persian as their court language. 

Jackal trying to lead the Lion astray

There is thus Persian literature from Iran, Mesopotamia, Azerbaijan, the wider Caucasus, Turkey, western parts of Pakistan, India, Tajikistan and other parts of Central Asia. 

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. At the same time, not all literature written in Persian is written by ethnic Persians or Iranians, as Turkic, Caucasian, and Indic poets and writers have also used the Persian language in the environment of Persianate cultures.