In the early decades of the twentieth century, interpretive models based on evolutionary analogies gave way to inferences built on historically contingent processes of migration, innovation, and diffusion. This understanding of culture was aptly titled the ‘historical particularist school’ and its archaeological advocates culture historians. This shift in interpretive modeling had its roots in a new atomistic understanding of culture as comprised of discrete units known as culture traits. Rather than looking at societies as rungs on a rationally progressive ladder of history, ‘culture historians’ instead envisioned cultures as temporary clusterings of discrete traits flowing through time. Later critics of this approach have referred to it as the water flow model of culture. As ideal (beliefs, values, emotions) and material traits (symbols, houses, tools) flowed through time and across space, they formed and re-formed different cultures. Archaeologists saw their science as an historical one that consisted of identifying, tracking, and explaining these configurations of traits.
Initially in Europe, where many nations could trace their populations to local prehistory, earlier evolutionary approaches were transformed into nationalist culture histories. Later, under the influence of Gordon Childe, these tendencies were muted in favor of interpretations that were international and emphasized the innovation and spread of functionally useful traits.
In the Americas where archaeologists were by and large derived from immigrant populations rather than indigenous Native Americans communities, nationalist archaeologies were less pronounced. Archaeology was situated in anthropology departments rather than archaeology or history departments as it was in Europe. In the Americas, archaeology was identified with the ethnological study of aboriginal peoples. While stage-based approaches generated interesting cross-cultural patterns, they were typically weak with respect to specific societies. A trait-based approach to cultures in archaeology went hand in hand with an emphasis on detailed ethnographic observation and particularist studies in American anthropology as a whole.
A number of early North American culture historians were also ethnographers, and their creative urge to apply historical particularist theory to archaeology stimulated their archaeological students and colleagues to see new possibilities in seriation and stratigraphic techniques that had been known for some time. Indeed, they became topics of theoretical consideration.
Culture historians realized that an atomistic approach to culture and history provoked and facilitated a much finer parsing of material trait variability into archaeological cultures. The interpretive model of an archaeological culture defined by clusters of styles of ceramics, lithics, housing, grinding stones, etc., focused attention directly on the particulars of prehistoric cultures and away from ethnological stages. As a result, culture historians dramatically expanded knowledge of the spatial and temporal patterning of material culture in the archaeological record. To explain these patterns, interpretive modeling turned to discussions of diffusion, innovation, and migration.
This was particularly useful in the context of the New World where well-known historical changes were not easily accommodated into the progressive evolutionary models of earlier scholars. For example, it had long been known that ethnohistoric Native American cultures seemed ‘less evolved’ than those associated with prehistoric mound building in the eastern United States. Similarly, the famous horse nomad societies of the North American plains had clearly emerged after the introduction of horses by Spanish and other European explorers. As Clark Wissler noted in his critique of evolutionary theory, many of these Plains societies seem to have de-evolved from barbarian farmers to savage hunters during the colonial period. In the Old and New Worlds, this atomistic understanding of culture led to the majority of spatial temporal designations (i. e., phases) still in use today, albeit often stripped of their culture historical assumptions.
Although successful, and one of the more unified examples of archaeological method and theory, culture history also had its weaknesses, especially when compared with the emerging functionalist social theory associated with anthropology and other social sciences of the time. Ironically, while ethnologists such as Wissler had justified this theoretical approach by appeals to ethnography and history, ethnographic analogy was less central to the interpretive models of culture historians. The function of traits was perceived as relatively self-evident (houses were shelters, ceramics stored food, arrows were projectiles, etc.), and therefore questions about artifact uses and activities were not emphasized. Instead, how artifacts were acquired and transmitted across time and space drew intellectual energies.
Since the processes creating such distributions were already known through migration, innovation, and diffusion, explicit integration of ethnographic analogies in interpretation were unnecessary. Not surprisingly, as culture-process-oriented questions about ecology, social organizational or conflict began to crop up in the changing theoretical landscape of the social sciences, archaeological contradictions between archaeological and anthropological interpretive models became a theoretical concern. Initially, this contradiction between the archaeological study of culture and that of anthropologists and historians was addressed by seeking to define material traits that served as process markers.
Gordon R. Willey, for example, influenced by Julian Steward’s ecological theory, defined ‘settlement pattern’ as a trait in his Florida Archaeology. Such comprises, however, were cumbersome and archaeologists began to actively push the boundaries of particularist theory in the 1930s and 1940s.