Major Cultural Periods
These are the major named cultural/time periods used by archeologists as a broad chronological or culture history framework for the 13,000-year prehistoric span. The most basic divisions Paleoindian > Archaic > Formative (or Late Prehistoric) were originally conceived of as successive evolutionary stages of increasing cultural complexity. These stages are seen as a simplistic notion today, but the 3-part division of prehistoric time is still widely followed as a general framework (see FAQ “Periods” ). The three basic divisions (sometimes called “eras") are divided into two or three periods (early and late or early, middle, and late).
Each period is characterized by distinctive assemblages (consistent groupings) of certain types of artifacts (especially projectile points) and widely shared cultural patterns, such as a predominance of bison hunting or village life, or technological changes, such as the introduction of the bow and arrow weapon system. The naming of the periods is based on classification schemes developed in the 1950s that are now considered outdated; still, archeological tradition lives on and the general meaning of these terms is widely understood.
We present different chronological frameworks for the Eastern and Western parts of the Trans-Pecos Mountains and Basins region in keeping with archeological practice, and in recognition of the fact that the culture histories of the eastern and western parts of the region were noticably different, particularly over the final 1500 years of prehistory. With the notable exception of the La Junta district, the eastern two-thirds or so of the Trans-Pecos region (roughly east and south of the Delaware Mountains in central Culberson County) was home to small foraging (hunting and gathering) societies throughout prehistory. In contrast, more settled village life based on agriculture developed in the western Trans-Pecos around 1800 years ago (A.D. 200). Culturally, the western Trans-Pecos was part of the American Southwest.
The western Trans-Pecos is also distinctive because a great deal more archeological research has been carried out there and in adjacent southern New Mexico than has been done in the much larger eastern Trans-Pecos. Part of this disparity is because archeologists long have been attracted to Jornada Mogollon village sites in the El Paso area and part of it is that El Paso is the largest and oldest city in the region (more people = more archeologists; more development = more archeology). But the single biggest factor is the presence of large military bases (e.g., Fort Bliss, White Sands), which have seen many archeological investigations because of federal laws that seek to minimize and mitigate damage to cultural resources.
In contrast, most of the eastern Trans-Pecos is undeveloped private ranch land with very low population density. Both the federal and state governments also have large parks there (Big Bend National Park and Big Bend Ranch State Park) where cultural resources are protected. Without many people and with only a small university (Sul Ross State University), most of the eastern Trans-Pecos remains largely archeologically unknown in comparison with most other areas of the state (even compared to the South Texas Plains). In recognition of this, the Center for Big Bend Studies at Sul Ross has launched a major regional research program (the Trans-Pecos Archaeological Project), that is yielding new insight on many fronts. But there is still a long way to go.
In both the eastern and western Trans-Pecos the first 9,000 to 10,000 years of prehistory are very poorly known compared to the latter 3,000 to 4,000 years. This same statement generally holds true for much of North America, but it is even more the case for the Trans-Pecos because of two factors. The first is that, in general, the Chihuahuan Desert has always been a relatively tough place for pre-industrial people to live because deserts have low biomass (relatively few plants and animals) simply because they are dry. In other words, the Trans-Pecos was home to fewer people through time in comparison to wetter/cooler adjacent regions such as the Edwards Plateau, the Southern Plains, and most of the Southwest (where mountain snows provide annual runoff into the intermontane desert basins). Through time more people lived in the Trans-Pecos because, overall, more people lived in North America and some of them learned to exploit desert resources effectively. The second is that older sites are rarely preserved as well as later sites, and they are often harder to find, particularly the fleeting traces left by highly mobile peoples.
Because of these factors, the chronology of the long-lived Archaic era in the Trans-Pecos is very poorly known. Comparatively speaking, there are only a handful of radiocarbon assays dating before 4,000 B.P. (about 2,500 B.C.) compared to those dating after 4,000 B.P. Because the dating of the Paleoindian era has been firmly established by many investigations in adjacent regions, we can safely assume that similar cultures in the Trans-Pecos date to approximately the same periods because we find the same kinds of time markers (lanceolate dart and spear points). But during Archaic times there are many more kinds of time markers and evidence of different kinds of cultures and "local adaptations" to localized ecological settings. Frankly, we do not yet know "what happened when" during the entire Early Archaic period because very few dated, stratified sites with Early Archaic deposits have been studied (and few are even known to exist).
Lacking good data, archeologists in the region have tended to stick with crude approximations of when the Early Archaic period began and ended based on outdated guesses made decades ago before radiocarbon calibration methods were well developed. Thus published and often-repeated chronological schemes show the Early Archaic as beginning around 6,000 B.C., meaning that the Late Paleoindian period has been depicted as lasting several thousand years longer in the Trans-Pecos than is known to have been the case in adjacent, better known regions. Here, we have chosen to use an arbitrary starting date of about 8,000 B.C. for the Early Archaic because we think this is a more reasonable approximation based on research in adjacent regions.
As research progresses in the Trans-Pecos Mountains and Basins and better chronological information is gained, archeologists will refine their cultural concepts of time and develop more precise chronologies with subperiods or smaller intervals.
For present purposes, just think of these periods as attempts to divide up prehistory into convenient blocks of time useful for outlining broad cultural patterns. We’ll never be able to discuss prehistoric patterns from year to year or decade to decade except in very rare circumstances. Even century-to-century patterns are very hard to unravel. Dating techniques just aren’t that sophisticated for most of prehistory. To really understand what happened over the 13,000 years of prehistory in the Trans-Pecos Mountains and Basins, especially the first 9,000-10,000 years, will require hundreds of radiocarbon-dated samples from well-documented contexts and a thorough geographic coverage of the region. This will probably take many decades of additional research and will continue to prove more difficult to achieve here than in regions where the archeological record is better preserved.
The most up-to-date summary of the prehistory of the Trans-Pecos is listed below and may be downloaded as a PDF file.
Miller, Myles R., and Nancy A. Kenmotsu
2004 Prehistory of the Jornada Mogollon and Eastern Trans-Pecos Regions of West Texas. In The Prehistoric Archeology of Texas, edited by Timothy K. Perttula, pp. 205-265. Texas A&M University Press, College Station. Download 
