ABSTRACT
One of the odder features of the Persian sources on the history of the Mongol period is the vagueness and comparative rarity of references to the ‘Great Yāsā of Chingiz Khān’. This struck me with renewed force after reading Professor David Ayalon’s articles on the Yāsā in Studia Islamica. 1 My suspicions about the whole matter having thus been aroused, it seemed to me that it might be an interesting exercise to look again at the origin and nature of the Yāsā before trying to estimate how Mongol law worked in the Īlkhānate. And so, as I hope to show in this paper, it proved.
