The answer is; "Roman Pope Urban II rally Christians to help Byzantine emperor Alexius I to drive the Muslim Turks from the Holy Land".
The Council of Clermont refers to a gathering for reformation of church which is called by Pope Urban II in 1095, which, because of a demand by envoys from the Byzantine emperror Alexius I Comnenus to help the Greeks against the Muslim Turks, turned into the event for starting the First Crusade. Urban II urged the French knights at Clermont to protect the Holy Land from the Turks, shutting his discourse with the words "God wills it," which turned into a battle cry of the crusaders; the occasion initiated the medieval religious wars against the Muslims.