The pope got scared by the suljuks trying to take over Constantinople. Pope calls for European knight to take up the cross and crusade.
Causes of the crusades pt 2
They try to unify with other Christians. The Crusades began as a response to the threat posed by the Seljuks. Many emperors appealed to Pope Urban II for help.
After a month of fighting, the city surrendered. The victorious Crusaders killed most of the people who had fought against them. Several European nobles led the First Crusade. Around 100,000 Crusaders fought their way through Anatolia and headed south toward Palestine. In June of 1098, the Crusaders laid siege to the city of Antioch, in Syria, which was protected by a ring of walls.
The second crusades
That Crusade ended in failure. An army from Germany was badly defeated in Anatolia. A second army, led by the king of France, arrived in Jerusalem in 1148. About 50,000 Crusaders marched on the city of Damascus, which was on the way to Edessa.
The third crusade
By the 1180s, the great sultan Salah al-Din (SAL-eh ahl-DEEN), called Saladin by Europeans, had formed the largest Muslim empire since the Seljuks. Salah al-Din united Egypt, Syria, and other lands to the east. He led a renewed fight against the Crusaders in the Holy Land and quickly recovered most of Palestine.
the later crusades
The Crusades continued for centuries. Some Crusades were popular movements of poor people, rather than organized military campaigns. In 1212, for example, thousands of young peasants from France and Germany marched in a Children's Crusade. Few, if any, ever reached the Holy Land. None of the later Crusades succeeded in recapturing Jerusalem. Muslims, meanwhile, were gaining back the land they had lost and took Acre, the last Crusader city, in 1291. This victory ended some 200 years of Christian kingdoms in the Holy Land.