Final answer:
The Crusades gave hope in the West of reuniting the two churches and imposing Roman Catholic authority on the Orthodox Church.
Step-by-step explanation:
The Crusades had significant effects on the Great Schism, which refers to the division between the Eastern Orthodox Church and the Roman Catholic Church. In the West, there was hope that the Crusades would help reunite the two churches under the authority of the pope and impose the Roman Catholic Church's vision of a reformed church on the Orthodox Church. The Western leaders saw the Crusades as an opportunity to strengthen the authority of the pope and bring the Eastern Church under the Western Church's control.
In the West, there was hope that the Crusades would unify the divided Christian churches and restore papal authority, especially in light of the Great Western Schism. Pope Urban II saw the Crusades as an opportunity to aid the Byzantine Empire, recapture the Holy Land, and strengthen the papacy's position. However, these hopes did not significantly bridge the divide caused by the Great Schism of 1054.
The hope in the West regarding the effects of the Crusades on the Great Schism was that they would serve as a unifying factor for the divided Christian churches. Specifically, it was hoped that the efforts of the Western Church to aid the Byzantine Empire and recapture the Holy Land from Islamic rule would help mend the rift and restore unity under the papacy. These hopes were in line with the aspirations of figures like Pope Urban II, who tied the idea of military expedition to the recovery and reform of Christian lands and institutions.
During the Great Western Schism (1378–1417), which saw multiple claimants to the papacy, the reputation of the papacy was significantly damaged. Pope Urban II's call for the First Crusade in part also aimed to consolidate his position against a rival pope and bolster the image and authority of the papacy overall by also reaching out to the East. However, the underlying issues between the Eastern Orthodox and Western Roman churches were deep-seated and historical, and the Crusades ultimately did little to resolve the tensions of the Great Schism of 1054.