Towards the end of the thirteenth century the Nestorian monk, Raban Sauma, together with his disciple Mark, began a journey from Mongol-controlled China to Jerusalem. Though they never reached their destination, due to military unrest, they did reach Baghdad, where Raban Sauma spent many years before later becaming Ilkhanid ambassador to Europe. His disciple, Mark, became the Nestorian Catholicus. Sauma's account of his travels provides unique information on both the Ilkhans of Persia and their dealings with the Mongol Christians as well as the events that led to the downfall of the Nestorian...