The capture of Jerusalem in July 1099. In the foreground the battle is at its height, with armored knights scaling on ladders. In the background the Passion of Christ is revealed in the Betrayal, Flagellation, Carrying of the cross, cruxifixion and Entombment; early 14th century. The First Crusade (1096-99) was the first of a number of crusades that attempted to capture the Holy Lands, called by Pope Urban II. It started as a widespread pilgrimage in western christendom and ended as a military expedition by Roman Catholic Europe to regain the Holy Lands taken in the Muslim conquests of the Levant (632-661). It was launched on November 27,1095 by Pope Urban II responding to an appeal from Byzantine Emperor Alexios I Komnenos, who requested that western volunteers help to repel the invading Seljuq Turks from Anatolia. An additional goal soon became the principal objective - the Christian reconquest of the sacred city of Jerusalem and the Holy Land and the freeing of the Eastern Christians from Muslim rule. During the crusade, knights, peasants and serfs from many nations of Western Europe travelled over land and by sea, first to Constantinople and then on towards Jerusalem. The Crusaders arrived at Jerusalem, launched an assault on the city, and captured it in July 1099, massacring many of the city's Muslim, Christian, and Jewish inhabitants.