Джами ат-таварих
A rich civilization developed under these "little khans", who were originally subservient to the Yuan emperor, but rapidly became independent. Architectural activity intensified as the Mongols became sedentary, and retained traces of their nomadic origins, such as the north–south orientation of the buildings. At the same time a process of "iranisation" took place, and construction according to previously established types, such as the "Iranian plan" mosques, was resumed. The art of the Persian book was also born under this dynasty, and was encouraged by aristocratic patronage of large manuscripts such as the "Jami' al-tawarikh" by Rashid-al-Din Hamadani. New techniques in ceramics appeared, such as the lajvardina (a variation on luster-ware), and Chinese influence is perceptible in all arts.