When we survey that multitude of nations spread over North and South America, eastward of the Cordilleras of the Andes, we fix our attention particularly on those who, having long held dominion over their neighbours, have acted an important part on the stage of the world. It is the business of the historian to group facts, to distinguish masses, to ascend to the common sources of many migrations and popular movements. Great empires, the regular organization of a sacerdotal hierarchy, and the culture which that organization favours in the first ages of society, have existed only on the high mountains of the western world. In Mexico we see a vast monarchy enclosing small republics; at Cundinamarca and Peru we find pure theocracies. Fortified towns, highways and large edifices of stone, an extraordinary development of the feudal system, the separation of castes, convents of men and women, religious congregations regulated by discipline more or less severe, complicated divisions of time connected with the calendars, the zodiacs, and the astrology of the enlightened nations of Asia--all these phenomena in America belong to one region only, the long and narrow Alpine band extending from the thirtieth degree of north latitude to the twenty-fifth degree of south. The migration of nations in the ancient world was from east to west; the Basques or Iberians, the Celts, the Germans and the Pelasgi, appeared in succession. In the New World similar migrations flowed from north to south. Among the nations that inhabit the two hemispheres, the direction of this movement followed that of the mountains; but in the torrid zone the temperate table-lands of the Cordilleras had greater influence on the destiny of mankind, than the mountains of Asia and central Europe. As, properly speaking, only civilized nations have a history, the history of the Americans is necessarily no more than that of a small portion of the inhabitants of the mountains. Profound obscurity envelops the vast country which stretches from the eastern slope of the Cordilleras towards the Atlantic; and for this very reason, whatever in that country relates to the preponderance of one nation over others, to distant migrations, to the physiognomical features which denote a foreign race, excite our deepest interest.