Arab Conquest of the Holy Land.--Swarm of Pilgrims in the Year 1000.--Turkish Invasion of Judea.--Persecution of the Christians.--Pope Silvester II.--Expedition of the Pisans and the Genoese.--Peter the Hermit.--Letter from Simeon the Patriarch to Pope Urban II.--First Crusade.--Expedition of “Gautier sans Avoir.”--Godefroy de Bouillon.--The Kingdom of Jerusalem.--Second Crusade.--St. Bernard.--Third Crusade: Philip Augustus and Richard Cœur de Lion.--Fourth Crusade.--Fifth and Sixth Crusades.--Louis IX. turns Crusader.--Seventh Crusade.--St. Louis taken Prisoner.--Eighth and last Crusade.--Death of St. Louis.--Results of the Crusades. “Jerusalem,” says Jacques de Vitry, Bishop of Ptolemais in the thirteenth century, and one of the most eloquent historians of the Crusades, “Jerusalem is the city of cities, the saint of saints, the queen of nations, and the princess of provinces. She is situated in the centre of the world, in the middle of the earth, so that all men may turn their steps towards her; she is the patrimony of the patriarchs, the muse of the prophets, the mistress of the apostles, the cradle of our salvation, the home of our Lord, and the mother of the faith, as Rome is the mother of the faithful. She is chosen and hallowed by the Almighty, who placed his feet upon her, honoured by the angels, and visited by all the nations of the earth.” A poet of the same period declares, in a burst of fervent inspiration: “She attracts the faithful as the magnet attracts the steel, as the sheep attracts the lamb with the milk of its teats, as the sea attracts the river to which it has given birth.” Under the influence of this belief it is easy to understand the powerful interest which, in the eyes of the whole Christian world, was attached to a corner of the globe so marked with the impress of the Almighty, and the object of so much veneration. Since the conversion of Constantine I., which so gloriously signalized the triumph of the cross, and while the ostentatious but feeble successors of that great emperor were preparing the decline of the empire of Byzantium, Jerusalem had frequently been forced to submit to infidel profanations, and the Western Christians, in their visits to the holy places, had, in consequence, many times encountered painful and almost insurmountable obstacles.