This present study had its genesis as a Ph.D. dissertation, which was submitted to the Senate of the Hebrew University of Jerusalem in February 1990. I wish to take this opportunity to express my deep gratitude to my supervisors, Professor David Ayalon and Dr. Peter Jackson, for having given unstintingly of their time and knowledge over a period of many years, even after my formal status as a student was ended. I would also like to thank the following: Dr. D.O. Morgan, for his sound advice and helping hand; Professor M. Sharon, for his encouragement and counsel over the years; Mr. A.H. Morton, who first introduced me to the Īlkhānid sources; Mr. R. Irwin, who contributed both helpful criticism and countenance, perhaps more than he is willing to admit; Professor U. Haarmann, who supplied me with an important microfilm at very short notice; Professor A. Khazanov, who read a very early version of chapter 1; Professor R.P. Lindner, for reading a draft of chapter 10.1 would also like to acknowledge the assistance of Professor E. Kohlberg for his advice regarding publishing this work. In addition, my thanks are due to Dr. Ellenblum for his translations from Latin, Professor M. Erdal for his help in transliterating Turkish and Mongolian names and terms, and Mr. D. Dector for assistance with Russian material. I am also grateful to Ms. Tamar Sofer and Ms. Noa Nachum of the Cartographic Laboratory of the Hebrew University of Jerusalem, for the maps which they produced for this volume, as well as to Ms. Sally Ayrton and Ms. Roza el-Eini for their careful reading of this study and their judicious comments.