Thus the Crusades are really worthy to be chronicled by historians above anything else which took place in the Middle Ages, since they gave birth to mighty agencies, which still are vital forces in society,--even as everything in American history pales before that awful war which arrayed, in our times, the North against the South in desperate and deadly contest; the history of which remains to be written, but cannot be written till the animosities which provoked it have passed away. What a small matter to future historians is rapid colonization and development of material resources, in comparison with the sentiments which provoked that war! What will future philosophers care how many bushels of wheat are raised in Minnesota, or car-loads of corn brought from Illinois, or hogs slaughtered in Chicago, or yards of cloth woven in Lowell, or cases of goods packed in New York, or bales of carpets manufactured in Philadelphia, or pounds of cotton exported from New Orleans, or meetings of railway presidents at Cincinnati to pool the profits of their monopolies, or women's-rights conventions held in Boston, or schemes of speculators ventilated in the lobbies of Washington; or stock-jobbing and gambling operations take place in every large city of the country,--compared with the mighty marshalling of forces on the banks of the Potomac, at the call of patriotism, to preserve the life of the republic? You cannot divest war of dignity and interest when the grandest results, which affect the permanent welfare of nations, are made to appear. The Crusades, as they were historically developed, are mixed up with the religious ideas of the Middle Ages, with the domination of popes, with the feudal system, with chivalry, with monastic life, with the central power of kings, with the birth of mercantile States, with the fears and interests of England, France, Germany, and Italy, for two hundred years,--yea, with the architecture, commerce, geographical science, and all the arts then known. All these principalities and powers and institutions and enterprises were affected by them, so that at their termination a new era in civilization began. Grasp the Crusades, and you comprehend one of the forces which undermined the institutions of the Middle Ages.