Chaco Culture National Historical Park

Origins of the Chaco Great Houses

At one time it was thought that the great houses of Chaco Canyon represented the beginning of Anasazi glory. Today, with many years of research and a greater understanding of Chacoan culture, archaeologists believe that great house architecture was the peak of Anasazi culture. The beginning can be traced back into the Basketmaker III period and its final manifestations lie in pueblos such as Second Mesa and Acoma. The 50-year drought that probably caused the decline of Chaco culture sent its people south, east and west to establish new settlements where they continued the Chaco tradition and the next stage in the evolution of Anasazi culture.

Pit houses were a common form of dwelling across much of Native North America, including the Southwest. They were easy to build, relatively cool in the summer and warm in the winter but not very defensible, and were for protection from the elements, not from enemies. It was only in the area of Chacoan influence that pit house communities developed into the unique structures known as great houses.

In the late 400s of the Common Era, two large pit house villages were built at either end of what is today Chaco Culture National Park. In "The Rise of Early Chacoan Great Houses," Thomas C. Windes states that these sites spanned an area one to two miles long starting at the canyon bottom and extending southward into the plains. Each village contained more than 100 pit houses and a community great kiva. After about a century the inhabitants burned their great kivas and left.

The origins of Chaco architecture, according to Windes, may be found as far north as Dolores, Colorado where the McPhee Pueblo, built between 780 and 860 CE shows some of the inspiration for Chaco's great houses. The builders of McPhee Village experimented with masonry walls. What began as a crescent shaped structure having 20 to 25 rooms with jacal walls built on sandstone slab footings, was enlarged about 860 CE to a stone masonry structure containing about 100 rooms (housing for 18 to 20 families) with a central stone pit house-not a great kiva, Windes emphasizes-as the focal point for community activities and rituals.

To the south of Chaco in the Red Mesa Valley, between 750 and 900 CE a group of pit house dwellers began to construct small masonry houses at the base of the cliffs. Then in the late 900s to 1000s, innovation led them to erect a two story building of shaped limestone blocks containing large rooms set around a central plaza. This new form of architecture appears at most of the villages in Red Mesa Valley. The same architectural style appears in northern communities across the Chacoan world. There is still disagreement about the inspiration for this new architectural style.

The first archaeologists to see Chaco Canyon believed that its architecture had been influenced by that of Central America. They cited rubble-cored masonry, colonnades of square columns, circular structures in the shape of tower kivas, and alignment of buildings and architectural features for observing and recording astronomical data, to list but a few characteristics shared by Chaco great houses with their southern neighbors. Too, copper bells, shell trumpets and bracelets, macaws and parrots, ceremonial wooden canes, decorative techniques in cloisonné and mosaic were common to both Chaco and the south.

On the other hand, Stephen H. Lekson and others, argue that Chaco architecture evolved from regional pueblo construction, not from Mesoamerican influence.

What is certain is that by about 700 to 850 A.D. (Pueblo I Period) a distinctive new style of building was emerging. Pit houses began to be accompanied by surface houses where timber was gradually eliminated from wall construction in favor of stones held together with mud mortar.

By 1100 CE, three different styles of architecture coexisted in Chaco Canyon: what is called the Bonito phase--the 12 great houses; the Hosta Butte phase represented by many small houses built in the same puebloan style found throughout the region, and; the McElmo phase, represented by a small number of great houses built later and having the same masonry style as the buildings at Mesa Verde. It appears to mean that at one and the same time that many families lived in and around Chaco Canyon in the small Hosta Butte style houses, a few families lived in the great houses. And, it is speculated that finding the Hosta Butte, Bonito and McElmo style structures together indicates that the different groups of Anasazi people lived peacefully together.

At some point human enemies appeared in the vicinity of Chaco Canyon causing the denizens of the great houses to reduce or eliminate exterior wall openings. In some cases the only type of entrance was by means of a removable ladder extending through an aperture in the roof. Originally, archaeologists had speculated that migrating Athabascan peoples such as the Navajo and Apaches may have caused the decline of Chaco culture, but current theory is that they did not arrive in Northwestern New Mexico until several centuries after the abandonment of Chaco Canyon. It's possible that migrating Shoshonean people may have come into the area, but the most likely threat, according to the Listers, is other groups of Anasazi.

Quick lecture on Chaco masonry styles: In order to follow archaeological thought on the origins and development of Chaco architecture, it's necessary to have a basic understanding of the various masonry styles.

The National Park Service publishes an attractive and informative brochure on Chaco Canyon. In it they define the earliest style of masonry, found in Pueblo Bonito's oldest walls, as a wall made of unshaped stones laid horizontally in a heavy mud mortar.

This style was superseded by the core and veneer style wall using an inner core of rubble between veneers of fairly thin facing stone. The walls were tapered as they increased in height and were faced with large blocks of sandstone chinked with many smaller stones set in mortar.

During the 11th century, more sophisticated styles of core and veneer masonry were developed which used shaped sandstone blocks mortared with mud, or shaped sandstone blocks chinked with small stones, and separated by horizontal bands of smaller stones set in mortar.

The McElmo style of masonry uses a thin rubble core and thick veneers of shaped stones chinked with smaller stones and mud. However, the stones are not as carefully shaped or placed as are earlier styles of core and veneer.

Despite the attractive textured appearance of Chacoan core and veneer construction, evidence shows that most of these walls were originally covered over with a mud plaster.

Copyright 2005 by Lynne D. Escue "Reproduction without permission prohibited."