The first people to inhabit Ferdows were traditionally a group of Sagartians. Toon was a famous and thriving city both before and during the Islamic era, until the raid of the Mongols. It was one of the most prominent cities of Ghohestan, along with Qaen; Nasir Khusraw mentioned Toon as a large city in the 11th century. Toon was plundered and destroyed by the Mongols in 1239. After the Mongol invasion, Toon eventually recovered and became one of the major cities of Ghohestan again. Marco Polo mentioned the south Khorasan region as "Toonoqaen", apparently in reference to the two largest cities, Toon and Qaen.