Final answer:
Pope Urban II called for the First Crusade to assist the Byzantine Empire and to retake Jerusalem, while also seeking to unify the Western Church and demonstrate the papal power in Europe. The Crusade was both a response to geopolitical strife and a spiritual campaign marketed as an armed pilgrimage to reclaim a sacred Christian site.
Step-by-step explanation:
Reasons for Launching the First Crusade
Pope Urban II had dual motives for launching the First Crusade. His initial intention was to aid the Byzantine Empire against Turkish threats by reclaiming Jerusalem and aiding local Christians. Religiously motivated warfare was not new to Christianity or Islam, but the specifics of the Crusade fused powerful religious goals with political and social ambitions. The First Crusade served to unite Western Christians and provided a spiritual opportunity, promising salvation for those who took part.
Another significant objective for Urban was to unify the church under his leadership. He faced opposition from a rival pope, endorsed by the German emperor, which polarized the Christian landscape of Europe. The Crusade was a maneuver to rally Western Christians and demonstrate the pontiff's power beyond mere ecclesiastical influence, offering an outlet for the violence of the European aristocracy while consolidating the papacy's authority.
In the call to liberate the Holy Land, Pope Urban II also tapped into the imaginative power of Jerusalem as a focal point of Christian faith, framing it as not just a spiritual mission but also a righteous adventure to reclaim what was perceived as a sacred Christian territory.