In 1095, Pope called for a crusade to liberate the city of from Muslim control, promising that each crusader would receive entrance into heaven and . People had many reasons for joining a crusade, including to defend Christendom and to .

The pope who called for the First Crusade at the Council of Clermont in 1095 was Urban II. He urged Christians to fight to take Jerusalem from Muslim control and promised spiritual rewards to crusaders. Gregory I and Leo X were not the pope who made this call.

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