On this day in 1095, Pope Urban II called for Christian princes across Europe to launch a war against Muslims in order to reclaim the Holy Land, promising to all those who went forgiveness of their sins and to all who died in the expedition immediate entry into heaven. Between 60,000 and 100,000 people responded to Urban's call to march on Jerusalem. After gaining control of the city in July 1099, the Crusaders set up several Latin Christian states. It was, however, a short victory. Less than fifty years later, Muslims once again conquered Jerusalem. All told, Europe launched a total of seven major Crusades over nearly 200 years.
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