In these latter days the sum of differences in international character has been appreciably bound down by the constant process of adaptation and adjustment, and by exposure to like influences. The people of various countries are swayed by identical interests, they are absorbed in the same problems, and thrill with the same emotions; their classics are interchangeable, authorities in science are nearly alike for all, and they readily combine to make experiments and researches in common. Towards 1500, European nations, having been fashioned and composed out of simple elements during the thousand years between the fall of the Roman Empire and that of its successor is the East, had reached full measure of differentiation. They were estranged from each other, and were inclined to treat the foreigner as the foe. Ancient links were loosened, the Pope was no longer an accepted peacemaker; and the idea of an international code, overriding the will of nations and the authority of sovereigns, had not dawned upon philosophy. Between the old order that was changing and the new that was unborn, Europe had an inorganic interval to go through. Modern History begins under stress of the Ottoman Conquest. Constantinople fell, after an attempt to negotiate for help, by the union of the Greek and Latin Churches. The agreement come to at Florence was not ratified at home; the attempt was resented, and led to an explosion of feeling that made even subjugation by the Turk seem for the moment less intolerable, and that hastened the catastrophe by making Western Christians slow to sacrifice themselves for their implacable brethren in the East. Offers of help were made, conditional on acceptance of the Florentine decree, and were rejected with patriotic and theological disdain. A small force of papal and Genoese mercenaries shared the fate of the defenders, and the end could not have been long averted, even by the restoration of religious unity. The Powers that held back were not restrained by dogmatic arguments only. The dread of Latin intolerance was the most favourable circumstance encountered by the Turks in the Eastern Empire, and they at once offered protection and immunities to the patriarch and his prelates. The conquest of the entire peninsula, with the islands, occupied a generation, and it was good policy meanwhile to do nothing that would diminish the advantage or awaken alarm of persecution. Their system required the increase rather than the conversion of Christian subjects, for the tribute of gold as well as the tribute of blood. The Janissaries were selected among the sons of Christian parents, who became renegades, and who, having neither home nor family, no life but in camp, no employment but arms, became not only the best professional soldiers in the world, but a force constantly active to undo the work of pacific statesmen and to find fresh occasion for war. There were occasional outbreaks of blind ferocity,