Aztec Ruins National Monument, 318 acres (129 hectares), NW N.Mex., near Farmington; est. 1923. Ruins of a 12th-century Pueblo town contain interesting kivas, one of which has been completely restored. Pueblo culture reached a high level of achievement in this area. The ruins were named by early settlers who mistakenly believed that they were built by the Aztecs. See National Parks and Monuments, table.

Aztec, Indian people dominating central Mexico at the time of the Spanish conquest. Their language belonged to the Nahuatlan subfamily of Uto-Aztecan languages. They arrived in the Valley of Mexico from the north toward the end of the 12th cent. and until the founding of their capital, Tenochtitlán (c.1325) were a poor, nomadic tribe absorbing the culture of nearby states. For the next century they maintained a precarious political autonomy while paying tribute to neighboring tribes, but by alliance, treachery, and conquest during the 15th and early 16th cent. they became a powerful political and cultural group. To the north they established hegemony over the Huastec, to the south over the Mixtec and Zapotec and even ventured as far as Guatemala. Their subjugation of the people of Tlaxcala in the mountains to the east was bloody but only intermittent, and the Tlaxcala people later became allies of the Spanish against the Aztec. Only in the west, where the Tarascan Indians severely defeated them, did the Aztec completely fail to conquer.

The Aztec Civilization

By absorption of other cultural elements and by conquest the Aztec achieved a composite civilization, based on the heritage of Toltec and Mixteca-Puebla. They attained a high degree of development in engineering, architecture, art, mathematics, and astronomy. The Aztec calendar utilized a 260-day year and a 52-year time cycle. Aztec skill in engineering was evident in the fortifications of their island capital. The Aztec further developed sculpture, weaving, metalwork, ornamentation, music, and picture writing for historical records. Agriculture was well advanced and trade flourished.

The political and social organization was based on three castes—nobility, priesthood, and military and merchants. The priesthood was a powerful political as well as religious force. Aztec government was relatively centralized, although many conquered chiefs retained political autonomy; they paid tribute and kept commerce open to the Aztec. The Aztec had a large and efficient army. Prisoners of war were used for human sacrifice to satisfy the many gods of the Aztec pantheon, notably Huitzilopochtli, the chief god, who was god of war.

Spanish Conquest

When the Spaniards, under Hernán Cortés, arrived in 1519, the Aztec civilization was at its height. However, many subject Indian groups, rebellious against Aztec rule, were only too willing to join the Spanish. Initially, the invaders were aided by the fact that the Aztec believed them to be descendants of the god Quetzalcoatl. Montezuma, the last of the independent Aztec rulers, received Cortés, who made him prisoner and attempted to rule through him. The Aztec revolted, Montezuma was killed, and Tenochtitlán was razed (1521). Cuauhtémoc, last of the emperors, was murdered (1525), and the Spanish proceeded to subjugate Mexico.

Archaeological site, northwestern New Mexico, U.S. Located on the Animas River just north of the town of Aztec, it was established in 1923 and has an area of 0.5 sq mi (1.3 sq km). Mistakenly named by early settlers, the site actually contains the excavated ruins of a 12th-century Pueblo town. It was designated a World Heritage site in 1987.

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Nahuatl-speaking people who in the 15th and early 16th centuries ruled a large empire in what is now central and southern Mexico. They may have originated on the northern Mexican plateau before migrating to their later location. Their migration may have been linked to the collapse of the Toltec civilization. The Aztec empire, which at its height comprised roughly five to six million people spread over some 80,000 sq mi (200,000 sq km), was made possible by their successful agricultural methods, including intensive cultivation, irrigation, and reclamation of wetlands. The Aztec state was despotic, militaristic, and sharply stratified according to class and caste. Aztec religion was syncretic, drawing especially on the beliefs of the Maya. The Aztec practiced human sacrifice, an activity that sometimes reached mass proportions. The empire came to an end when the Spanish conquistador Hernán Cortés took the emperor Montezuma II prisoner and conquered the great city Tenochtitlán (modern Mexico City). Seealso Nahua.

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