boundaries were constantly changing as new tribes were brought under Aztec rule, or by successful revolt threw off the Mexican yoke. Clavigero, followed by Prescott, gives to the empire the territory from 18° to 21° on the Atlantic, and 14° to 19° on the Pacific, exclusive, according to the latter author, of the possessions of Tezcuco and Tlacopan. But this extent of territory, estimated at nearly twice that of the state of California, gives an exaggerated idea of Anáhuac, even when that term is applied to the conquered territory of the whole confederacy. The limits mentioned are in reality the extreme points reached by the allied armies in their successful wars, or rather, raids, during the most palmy days of Aztec rule. Within these bounds were several nations that were never conquered, even temporarily, by the arms of Anáhuac, as for example the Tlascaltecs, the Tarascos, and the Chiapanecs. Many nations, indeed most of those whose home was far from the central capitals, were simply forced on different occasions by the presence of a conquering army to pay tribute and allegiance to the Aztec kings—an allegiance which they were not slow to throw off as soon as the invaders had withdrawn. Such were the nations of northern Guatemala and Soconusco, whose conquest was in reality but a successful raid for plunder and captives; such the nations of Tehuantepec, such the Miztecs and Zapotecs of Oajaca, the latter having completely regained their independence and driven the Aztecs from their soil before the coming of the Spaniards. Other nations were conquered only in the years immediately preceding the Spanish conquest; instance the Matlaltzincas just west of Anáhuac, and the Huastecs and Totonacs of Vera Cruz. By their successful raids among these latter peoples, the Aztecs only sealed their own doom, making inveterate foes of the coast nations, whose services would have been most efficacious in resisting the fatal progress of the Castilian arms. But other tribes less warlike and powerful, or nearer the strongholds of
