Answer:
Pope Urban II.
Explanation:
Byzantine emperor Alexius I attempted to stop the Seljuk Turks advance and is forced to look west and appeal to Pope Urban II for help. For decades the Turks had been capturing outer regions of the Byzantine Empire and converting these lands. To save the Byzantine Empire, it became crucial to stop Turks. Emperor Alexius I sent a letter to Pope Urban II in 1093 asking him to send soldiers to his empire to help push out the Turks. In return, Pope Urban II united all knights, commoners, and soldiers in Europe to fights against the Muslims and to reclaim the holy land Jerusalem.