Casa Grande Ruins
Administrative History
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The significance of Casa Grande ruins lies in its prehistoric past when the builders and inhabitants achieved a sophisticated culture. Casa Grande fell within the heartland of an extensive prehistoric agricultural society. The Hohokam (a Pima Indian term meaning "those who have gone"), with their lengthy canal irrigation system, were masters of the desert.

The Hohokam culture did not suddenly appear. Its antecedents lay in a previous, local Archaic culture. These Archaic peoples, who appeared in the desert Southwest about 5500 BC, functioned as hunters and gatherers who depended upon wild plants and animals for their subsistence. Whether domesticated corn became available before 1000 BC or not, these people did not cultivate it because they had little need to invest their labor in such a crop when they could subsist by hunting and gathering. A growing population perhaps combined with some dry periods, however, began to outstrip the flora and fauna used for food. By 1000 BC, this situation forced the population to augment their ration by cultivating a small cob popcorn. By 500 BC regular corn appeared in the area and was crossed with the small cob popcorn. The prehistoric population in turn, crossed this hybrid with an eight-row flour corn several centuries later. About 350 BC, common beans (pinto, red, and navy) were introduced. The Archaic peoples' casual dry land cultivation, however, did not produce sufficient yields to supply the growing demand. To ensure crop yields in the Southwest required considerable attention. Such attention began to curb the mobility of these hunter/gatherer peoples. Decreased mobility only forced the people to place greater reliance on domesticated crops. This more sedentary life, in turn, depleted the wild resources in an area. Returning to a hunting and gathering way of life then became no longer viable. As a result, this Archaic culture began a slow transition into a hydraulic (water based) society which used irrigation to support its agriculture. By AD 300 this water-based culture appeared as the Hohokam. [1]

Archeologists have divided the Hohokam culture into the following approximate four periods. The four periods include: Pioneer, AD 300-750; Colonial, AD 750-950; Sedentary, AD 950-1175; and the Classic, AD 1175-1450. The Pioneer period found the Hohokam living as simple farmers in a series of small villages along the middle Gila River. Several factors determined the location of an early Hohokam village — good arable land, a suitable location from which the Gila could be tapped for irrigation water, and a shallow aquifer so that wells for domestic water need not be dug more than ten feet deep. Early Hohokam houses consisted of branches bent in a semi-circular fashion and covered with twigs, reeds, and mud. House locations had no consistency. Instead, they were placed in what has been called a rancheria style; that is, they were scattered randomly over an area of as much as a square kilometer. Irrigation canals at first were of simple construction which served only a small village and thereby did not require intervillage cooperation or a large, disciplined labor force to maintain them. Because of this uncomplicated situation, the early Hohokam lived a life in which all were equal without a central authority to direct them. [2]

Between AD 300 and 500 the Hohokam acquired a new group of cultivated plants from Mexico. These plants included first cotton and tepary beans followed by sieva and jack beans, green-striped cushaw squash, warty squash, and pigweed. The Hohokam also augmented their food with wild plants such as goosefoot seeds, saguaro fruit and seeds, carpetweed seeds, grass seeds, prickly pear cactus fruit and pads, mustard seeds, wild primrose roots, four-o'clock roots, cholla buds, cattail roots and catkins, cocklebur, and coyote melon. They hunted animals such as jackrabbits, cottontails, and mule deer. Some fish and clams from the Gila River and the canals varied their diet. [3]

In their everyday life, the early Hohokam used manos and metates to grind seeds into coarse meal for cooking. Cooking was accomplished in plain brown pottery. This same pottery supplied storage vessels and containers for the cremated remains of the dead. These Pioneer period people had ceremonies as attested by fired clay human and animal figures and the use of incense burners. Some basic regional trade occurred, especially to obtain shell from the Gulf of California which was used to fashion jewelry. [4]

In the Colonial period (AD 750-950) the population increased. Some villages grew larger as a more refined social system developed. Social ranking began to play a role, as later noted, because some graves had more ornate items associated with them. At the larger settlements, ball courts came into existence. Although these large, oval-shaped depressions varied in size, they served as a focal point for games and ceremonies. In daily life a distinctive red-on-buff pottery came to predominate. [5]

The Sedentary period (AD 950-1175) brought numerous changes to the Hohokam civilization as the population continued to increase. Villages became an altered rancheria style as clusters of three to five houses were grouped together all facing a common or courtyard area. Post reinforced caliche pit houses came into use. These courtyard segments became the basic unit of village life. Most activities occurred out-of-doors under adjacent ramadas as the houses played only a small part in day-to-day life. It was here that the women tended roasting pits or slow baked food in large earth ovens. The development of a more complex canal system altered society. Since expanded canals now served more than one village, it was necessary to develop a leadership to coordinate water distribution. From the new need for greater authority, elite classes arose. They, no doubt, received much of their prestige from religion. The platform mounds which appeared in the villages had some association with the elite members and religious ceremonies. Rulers, of course, required symbols of their position. As a result, craftsmen became another select group to occupy larger settlements. These artisans produced finer jewelry products of shell, stone, and bone as well as carved stone and fired clay figures. Hohokam craftsmen used acid etching long before its use in Europe. Textile work in cotton flourished as well. Traders, too, came to have an enlarged role as extensive trade developed from the Little Colorado River area in the north to Mesoamerica on the south. Items obtained from the southern part of Mexico included copper bells, mosaics, stone mirrors, and ornate birds like macaws. [6]

During the Classic period, which began about AD 1175, organizational changes began to occur. The population stabilized and perhaps declined somewhat. Some settlements were abandoned as the population shifted into fewer and larger villages. Rancheria style villages were no longer the favored arrangement. The focus became more compact villages with each of these units composed of walled compounds around a central zone or civic-ceremonial district. At Casa Grande Ruis National Monument the central district is identified by the ball court and community plaza surrounded by Compounds A, B, C, and D. A uniting of the canal systems into fewer and longer canals can possibly explain this reorganization of the villages. By AD 1300 canal consolidation also produced an extended level of managerial/religious authority centered in a few select villages. These centers of power could probably be identified with the construction of "Great Houses" as exemplified by the Great House in Compound A at Casa Grande Ruins National Monument. These multi-storied caliche buildings served more than managerial functions, for they were also associated with astronomical uses. The Classic period also witnessed a reduction in trade, especially in Mesoamerican items. Although red on buff ceramics remained the standard, some polychrome pottery, obtained in trade from Pueblo groups in what comprises present-day Arizona and New Mexico, made an appearance especially in the centers of power. [7]

All adjustments in Hohokam society were tied to the preservation of their irrigation based society. Nature, however, ultimately robbed them of their lifestyle. Between 1200 and 1350, periodic years of high volume river flow caused a deepening of the Gila River channel. These times were interspersed with periods of low water. Consequently, the Hohokam farmers found that their canal intakes along the river could no longer divert sufficient water for irrigation. Intakes had to be moved further upstream and thus it became a struggle to continue farming. One answer was the consolidation of canal systems combined with the extension of political and religious control. This situation seems to have been the case with the Casa Grande canal which was ultimately consolidated and extended to obtain water from a point on the Gila River eighteen miles to the northeast of that village. Following 1355 times got worse as more catastrophic flooding appears to have taken place. A failure of the managerial/religious system to deal with the situation seems to have resulted in a slow societal collapse. Sometime between 1355 and 1450 the Hohokam abandoned their large, central settlements. The social system became decentralized as groups moved into the desert or established small villages along the Gila River and founded the Piman-speaking tribes encountered by the Spanish at the end of the seventeenth century. [8]

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Last Updated: 22-Jan-2002