They did not disappear
The people often called the Anasazi did not vanish. Around 1300 CE they left the Four Corners region, where Colorado, Utah, Arizona and New Mexico meet, and moved to other areas, mainly the Rio Grande valley in New Mexico, the Hopi mesas and the Zuni area in Arizona and New Mexico. Their descendants are the Pueblo peoples who live in those places today, including the Hopi, Zuni, Acoma and the nineteen pueblos of New Mexico. The “mystery” is therefore really a question of why people left, and the archaeology offers a set of partial answers.
A note on names
“Anasazi” is a Navajo word usually translated as something like “ancestors of enemies” or “ancient enemies”. Archaeologists adopted it in the early twentieth century. Many Pueblo people object to it, and “Ancestral Puebloans” is now the preferred term in most scholarly and public writing. This article uses the older name where the title does, and the newer one elsewhere. The Pueblo nations have their own names and histories, and their oral traditions record the migrations as deliberate movements in a long journey.
Chaco Canyon
In Chaco Canyon, northwestern New Mexico, people built a set of large masonry buildings called great houses between about 850 and 1150 CE. Pueblo Bonito, the best known, had hundreds of rooms and rose several storeys. Straight roads linked Chaco to outlying communities. Chaco was a major ceremonial and regional centre, and goods such as turquoise, macaw feathers and shell reached it from far away, as did cacao residue found in vessels. Whether it was a city, a pilgrimage center or something else is debated.
Ancient DNA from burials at Pueblo Bonito has been interpreted as showing that a few individuals in an important burial area came from one maternal line over several centuries, suggesting that status was inherited. The finding is recent and still being discussed.
By about 1150 Chaco’s influence declined, partly during a long dry period, and building at the great houses largely ended. Many people moved to other places in the region.
Mesa Verde and the cliff dwellings
Further north, in southwestern Colorado, Ancestral Puebloans lived on Mesa Verde for centuries. In the late 1100s and 1200s they built homes in alcoves in the cliffs, including Cliff Palace, the largest such site. These villages were compact, with kivas, round rooms used for ceremonies, and storage space for maize. Living in alcoves may have offered shelter from weather, protection from enemies, or both; scholars disagree about the balance.
Why the Four Corners were left
The tree-ring dating of timbers from these sites, a method developed in the American Southwest by A. E. Douglass in the early 1900s, shows when buildings were constructed, and it also provides a record of rainfall. These records show a severe drought from about 1276 to 1299, known as the Great Drought. Farmers depended on rainfall to grow maize, so such a drought would have strained food supplies. Climate stress also affected other societies, as in the debate on Maya drought evidence, but drought alone does not explain the movement.
Other factors are discussed. Some earlier periods of drought in the region were survived. Population in the area had grown, and resources like wood and game may have declined. Evidence for violence in the 1200s, including fortified sites and skeletal remains showing trauma at some places, suggests that conflict or fear of conflict increased. Changes in religious and social organisation may have made new communities more attractive, and the new Pueblo villages in the south drew migrants. Most researchers think that a combination of environmental stress, social tension and the pull of better farming land caused the move, with different explanations fitting different valleys.
Where they went
The migration was gradual, not a single event, and it took place over decades in the late 1200s. People joined or founded villages along the Rio Grande, around Zuni and Acoma, and on the Hopi mesas. Pottery styles, architecture and burial customs at those sites show continuity with the north, and pottery seriation has been used to follow such connections. New forms of ritual and art, including those linked to kachina beliefs, developed in the new communities, though their origins are discussed.
Comparisons and context
Stories of abandoned sites often turn into tales of mystery. The tale of the Norse Greenland settlements ending, or the sweeping claim about a vanished people, are examples of how a move can be turned into a disappearance. The case of the Ancestral Puebloans is different, since the people have descendants who keep the memory. A comparable process of centre-building and decline occurred at Cahokia mounds in the Mississippi valley around the same time, though that story is separate.
Today
Mesa Verde, Chaco Culture and other sites are protected as parks and World Heritage Sites, and several are managed with the involvement of Pueblo and other Native nations. Ancestral Puebloan sites are ancestral places for living communities, and visitors are asked to treat them with respect.