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Soon, however, another usurper retook Constantinople. The Crusaders went in to reconquer the City. They did so with such cruelty that the Byzantines were totally outraged. The Latin army set up their own emperor and their own patriarch of Constantinople, making it part of the Western Empire in effect.
The Crusade had been totally sidetracked and, far from recovering the Holy Land, it did not even reach Egypt, it's first objective.
Frederick, somehow, managed by diplomacy to gain Jerusalem, Bethlehem and Nazareth but, because he had seemed unwilling to Crusade, the Pope refused to confirm the treaty so all he had gained, they threw away.
Louis, at this time, suffered from a dangerous illness and seems to have been in a coma. Just as people began to think that he had died, he awoke and asked for a Cross. He devoted himself to the Crusade and, apparently began at once to recover.
Louis left his kingdom in the hands of his mother, Queen Blanche, and raised an army. He reached Damietta, Egypt, in June 1249. The Crusade started off with some success but after a while things changed for the worse. Many were lost in a plague, some of their best commanders were lost. There was also famine which weakened the Crusaders - some apparently having to eat their horses to survive. The enemy opened the sluices of the Nile at a time of flood and many more were thus swept to their death. Louis became ill again and had to surrender to the Egyptians from whom he had to be ransomed at great cost.
After he had been away from France for six years he had to return when the news of his mother's death reached him in 1254. Sixteen years later he made a second attempt. He thought that the Arabs would join him to overthrow the Mongols but, on his arrival in Tunis, the Arabs attacked him instead. Soon both he and his troops were suffering from a variety of illnesses caused by the heat, lack of water and poor diet. He, himself, died in August 1270. His son Phillip returned to France with the bodies of his father, his brother, one of his own sons and his brother in law, the King of Navarre.
The Crusades had been, from beginning to end, a disaster. Whatever the motivation of the pious men who called for these "wars of the cross", they had embarked upon a course of action which had not been sanctioned by the Christ who had said, "Those who live by the sword will die by the sword."
In a final section on the Crusades I hope to be able to look at their overall significance for the history of the Christian Church and what lessons may be gleaned from them.