There were several more Crusades. None of them (unless we except the treaty of the excommunicated Frederick in 1229) ever reached Jerusalem. Some of them never even reached Palestine, being shamefully diverted to other purposes. Saddest of all was the Children's Crusade, when fifty thousand poor misguided children followed the Cross (like the Pied Piper of Hamelin) to slavery, dishonour, or death. But these form no part of the history of Jerusalem.
In 1244, we find Christian and Saracen making common cause in Palestine against the Kharezmians. These Mongols, who only appeared on the stage of history for a brief period of four years, swept through the country, captured Jerusalem, massacred all on whom they could lay hands, Moslem and Christian alike, and destroyed such sacred relics as they could find. Then, defeated by the Egyptians, they perished out of history as suddenly as they had appeared.
In 1291, the Christians, by this time reduced to their last stronghold of Acre, were finally expelled by the Moslems from Palestine--and that was the end of the Crusades. Europe became reconciled to the fact that the Kingdom of Christ is a Kingdom, not of the sword but of the soul. And so, the watchword by which the Crusades were inspired now became the consolation of their end--"Dieu le veut."
In 1400, Syria and Palestine fell under another Mongol invasion by Timoor the Tartar (Tamerlane). In 1517, Palestine was annexed to the Ottoman Empire under Selim I, of which Empire it has since formed an integral part. At the close of the eighteenth century, Napoleon marched through the country, defeating the Turks at Gaza and on the Plain of Esdraelon, but was forced to withdraw. In 1832, Mohammad Ali, having thrown off the Turkish yoke in Egypt, conquered Syria, but nine years later, through the action of the European Powers, the country was restored again to the Ottoman Porte.
In so far as any principles can be deduced from this history, they seem to show that Jerusalem, situated as it is, could never become the capital of a great Empire. On the other hand, this city, coveted by so many races and creeds, must be safeguarded by the arms and resources of some great Empire, or it can never remain at peace.