The Abandonment of Chaco Canyon

With the stunning amount of labor and resources that went into building Chaco, one can only beg the question: why abandon it?

When one hears about the Anasazi who “vanished”, it means the general abandonment of the Colorado Plateau around the year 1300 AD. The abandonment of Chaco was different; it was an orderly migration back to the Mesa Verde area, and occurred in approximately 1150 AD.

Migration was not a new concept to southwestern peoples; it was a way of life for their Anasazi brethren before, during, and after the Chaco period. The entire Colorado Plateau is littered with the final resting places of pit-houses, pueblos, caves, and cliff dwellings that were only occupied for a generation or two. Chaco had a stunning run of over 12 generations, very long by Anasazi standards. They survived droughts and environmental challenges, periods of scarce resources, and seemingly lived without violence for those 2+ centuries. And then, for reasons that can only be speculated upon, they slowly and deliberately sealed the Great Houses, ceremonially dismantled and burned the kivas and Great Kivas, and left.

It is true a great drought descended on the San Juan River Basin in 1130-1180, and that could have been a factor in the decision to migrate away. But these people had survived multiple severe droughts through the centuries; why would this one be the sole reason for leaving? Perhaps other factors were at play, and the drought served as the “final straw”.

Most civilizations end by either eroding from the inside out, or conquest by a stronger enemy. There is no evidence of warfare at Chaco, although the sealed doors, and reduced entry points to the Great Houses were once thought to be evidence of defensive measures against external enemies. Today it is generally accepted the doors were filled with masonry, and the kivas burned over a generation as a ceremonial cleansing, signifying the closing or sealing of whatever occurred at Chaco.

Without conquest by an outside enemy, that leaves an internal rotting of society as a leading suspect. Was there an increasing disparity between the rich and poor that reached a tipping point? Did trade with the south dry up and leave Chaco with reduced prestige? Did the outlying communities that supplied food to Chaco suffer agricultural calamity or did they collectively revolt against the leadership?