 Among Western Europeans , there had long been rumors and expectations that a great Christian ally would come from the East . These rumors circulated as early as the First Crusade ( 1096 – 1099 ) , and usually surged in popularity after the Crusaders lost a battle . A legend arose about a figure known as Prester John , who lived in far @-@ off India , Central Asia , or perhaps even Ethiopia . This legend developed a life of its own , and some individuals who came from the East were greeted with expectations that they might be forces sent by the long @-@ awaited Prester John . In 1210 , news reached the West of the battles of the Mongol Kuchlug ( d . 1218 ) , leader of the largely Christian tribe of the Naimans . Kuchlug 's forces had been battling the powerful Khwarezmian Empire , whose leader was the Muslim Muhammad II of Khwarezm . Rumors circulated in Europe that Kuchlug was the mythical Prester John , again battling the Muslims in the East . 
