Besides all these causes of mitigation, the constant journeys of the people of Europe to the Holy Land taught them gradually the customs of other nations; and in that age there was much good to be learned by a frequent intercourse with foreigners. The great want of Europe was civilization; the vices of the day were pretty equally spread through all countries, and the very circumstance of mingling with men of different habits and thoughts promoted the end to be desired, without bringing any great importation of foreign follies or crimes. Many useful arts, and many sciences, previously unknown, were also obtained from the Saracens themselves; and though in the crusades Europe sacrificed a host of her noblest knights, and spent immense treasures and energies, yet she derived, notwithstanding, no small benefit from her communication with Palestine. The state of that country, in the mean while, was every day becoming more and more precarious. The nations by whom it was surrounded were improving in military discipline, in political knowledge, and in the science of timing and combining their efforts, while the Christians were losing ground in every thing but courage. The military orders of the Temple and St. John were the bulwarks of the Latin kingdom of Jerusalem; but at the same time, by their pride, their disputes, and their ambition, they did nearly as much to undermine its strength at home as they did to support it with their swords in the field of battle. It would be endless to trace all the events in Palestine which brought about the third crusade, and to investigate minutely the causes which worked out the ruin of the Christian dominion in the Holy Land. The simple facts must be enough in this place. Although the crusade which went forth for the express purpose of delivering Edessa never even attempted that object, Joscelyn of Courtenay did not neglect to struggle for his lost territory, and gained some splendid successes over the infidels, which were all in turn reversed, by his capture and death in prison.[611] After his failure, the difficulty of keeping Edessa was so apparent, that the monarch of Jerusalem[612] determined to yield it to the Emperor Manuel Comnenus, on condition of his defending it against the Turks. Manuel, therefore, received the principality; but the weak and cowardly Greeks soon lost what the valiant Franks could not maintain; and before a year was over, Nourhaddin the Great, sultaun of Aleppo, was in full possession of Edessa and all its dependencies. Baldwin III., however, who had cast off the follies of his youth, and now displayed as great qualities as any of his race, more than compensated for the loss of that principality by the capture of Ascalon.[613]