Topic: What were the causes of the First Crusade? In the 900s Byzantium was powerful until Seljuk Turks came and invade their territories like Syria. The ongoing problems and the wars between the Byzantine and Seljuk Turks made angry the Byzantine Emperor Alexius I since he cannot cope with the Seljuks. With the increasing power of the Seljuk Turks, Byzantine Emperor Alexius I Comnenus sent a delegation to the Papuaienza in Italy and asked Pope Urban II help them against the Turks. Alexius I’s call was answered by the Pope and he called for a crusade to help the Byzantines and to conquer the city of Jerusalem at the French town of Clermont, where he held a Catholic Church council. Pope Urban gave a religious speech and promised them the Heaven for those who would go and fight in the holy war. This speech excited the people since everyone wants to go the Heaven. It also draws attention to the power of religious devotion in this age. The City of Jerusalem held a Holy significance to the Christian religion. The first of the Crusades began in 1906. By the end of 1096, the European armies started arriving in the Byzantine capital, Constantinople. After crossing the Bosporus, the crusaders marched towards the Seljuk 's capital in Asia Minor, the city of Nicaea, today İznik. Sticking to their oath to the emperor, the city of Nicaea was returned to the Byzantines. The main army walked on to the walls of Antioch, the city which nickname is the cradle of Christianity. In 1098,