By the time the Mongol army under Genghis Khan reached Balkh in 1220, the city had spent nearly six centuries as one of the leading centers of Sunni Islamic scholarship in the eastern Islamic world, its madrasas and mosques drawing students from across Central and South Asia. The Mongol conquest devastated it along with much of the wider region, and Balkh's population and standing scholarly institutions never fully recovered the preeminence they had held before, with regional religious and political prominence shifting substantially to other cities in the centuries that followed.
Even so, Balkh's Islamic religious legacy did not end with the Mongol destruction. The family of the poet and mystic Jalal ad-Din Rumi is traditionally said to have come from Balkh before migrating west ahead of the Mongol advance, a connection Rumi's own nisba, al-Balkhi, preserves in his name even though modern scholars are divided over whether he was actually born in Balkh itself or in the nearby town of Wakhsh. Balkh's religious history therefore runs in two directions from the Mongol catastrophe, backward toward a legendary Zoroastrian past and forward, more uncertainly, toward one of Sufism's most celebrated poets, a city whose sanctity has repeatedly been claimed by traditions that arrived generations, or centuries, after the events they commemorate.