whose name now first appears in history, the Acolhuas and Tepanecs soon rose to political prominence in the valley. The Acolhuas were the Chichimecs par excellence, or, as tradition has it, the Chichimec nation was absorbed by them, giving up its name, language, and institutions. The capitals which ruled the destinies of Anáhuac down to the fifteenth century, besides Culhuacan, were Tenayocan, Xaltocan, Coatlychan, Tezcuco, and Azcapuzalco. These capitals being governed for the most part by branches of the same royal Chichimec family, the era was one of civil intrigue for the balance of power and for succession to the throne, rather than one of foreign conquest. During the latter part of the period, Tezcuco, the Acolhua capital under the Chichimec kings proper, Azcapuzalco the capital of the Tepanecs, and Culhuacan held the country under their sway, sometimes allied to meet the forces of foreign foes, but oftener plotting against each other, each, by alliance with a second against the third, aiming at universal dominion. At last in this series of political manœuvres Culhuacan was permanently overthrown, and the Chichimec ruler at Tezcuco was driven from his possessions by the warlike chief of the Tepanecs, who thus for a short time was absolute master of Anáhuac.
But with the decadence of the Culhua power at Culhuacan, another of the tribes that came into notice in the valley after the fall of the Toltecs, had been gradually gaining a position among the nations. This rising power was the Aztecs, a people traditionally from the far north-west, whose wanderings are described in picture-writings shown in another part of this volume. Their migration is more definitely described than that of any other of the many who are said to have come from the same direction, and has been considered by different writers to be a migration from California, New Mexico, or Asia. Later researches indicate that the pictured annals are in-
