It is very probable that the Colhuas and Nahuas or Toltecs of the old books and traditions, together with the Aztecs, were all substantially the same people. They established in the country three distinct family groups of language, it is said, but the actual significance of this difference in speech has not been clearly determined. These unlike groups of language have not been sufficiently analyzed and studied to justify us in assuming that they did not all come from the same original source, or that there is a more radical difference between them than between the Sclavonic, Teutonic, and Scandinavian groups in Europe. These ancient Americans were distinct from each other at the time of the Conquest, but not so distinct as to show much difference in their religious ideas, their mythology, their ceremonies of worship, their methods of building, or in the general character of their civilization. If the Toltecs and our Mound-Builders were the same people, they probably went from Mexico and Central America to the Valley of the Mississippi at a very remote period, as Colhuan colonies, and after a long residence there returned so much changed in speech and in other respects as to seem a distinct people. The Aztecs appear to have dwelt obscurely in the south before they rose to power. They must have been at first much less advanced in civilization than their predecessors, but ready to adopt the superior knowledge and methods of the country they invaded. THEY CAME FROM THE SOUTH. It has sometimes been assumed that the Aztecs came to Mexico from the north, but there is nothing to warrant this assumption, nothing to make it probable, nothing even to explain the fact that some persons have entertained it. People of the ancient Mexican and Central American race are not found farther north than New Mexico and Arizona, where they are known as Pueblos, or Village Indians. In the old times that was a frontier region, and the Pueblos seem to represent ancient settlers who went there from the south. There was the border line between the Mexican race and the wild Indians, and the distinction between the Pueblos and the savage tribes is every way so uniform and so great that it is well-nigh impossible to believe they all belong to the same race. In fact, no people really like our wild Indians of North America have ever been found in Mexico, Central America, or South America.