Casa Grande Ruins
Administrative History
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Success at Casa Grande required more than construction of buildings and protection of the ruins. The first non-resident custodians conceived of their job as ruins protection and not as one to develop, promote, or interpret the monument. Frank Pinkley, who arrived in 1901, had other ideas. To him, the purpose of establishing the reservation was not just to protect the prehistoric remains found there. Pinkley also sought to publicize the monument and educate the public about the ancient culture that had occupied the site. An enlightened population would then not only know about the prehistoric past, but could serve as a support group for Casa Grande and other archeological sites.

Pinkley devised a number of means to attract people to Casa Grande as well as methods to educate them. His first thoughts were to develop an attraction by uncovering the ruins. He promoted excavation both for the visual effect and to obtain artifacts that could be displayed. Opening ruins also provided a means to learn more about the ancient people, and, therefore, furnish material for the interpretive story. In 1918, by the beginning of his second custodianship, experience had taught Pinkley additional means to promote the monument. Publicity was one key to attract visitation. Toward that end, Pinkley obtained an agreement with the state news agency to circulate stories about the monument. He spoke to social and business groups in the state and contacted the Southern Pacific Railroad to get that company to promote tourism to the monument. He worked with local women's clubs to obtain their help in publicizing the ruins. At his request, the National Park Service supplied copies of a general information pamphlet. He hoped to develop a mailing list from the names and addresses that people entered in his registration book, but lack of funds prevented Pinkley from producing either his mailing list or obtaining the assistance of Byron Cummings of the University of Arizona Anthropology Department and T. E. Farrish, the state historian, to produce additional pamphlets. In effect Pinkley took the same actions that Mather and Albright used to promote the national parks.

A. The Evolution of the National Park Service Interpretive Story

Interpretation or the presentation of a factual story provided one means to educate the public. Pinkley sought to greet all visitors and provide them with as much interesting information about the ruins and the inhabitants as possible. Over the years, tours, whether conducted by Pinkley or monument rangers, usually lasted from forty-five minutes to an hour. Occasionally, in the earlier days when visitation was less, Pinkley would linger for as long as two hours to answer the questions of interested parties. The principal theme Pinkley and others presented to visitors over the years dwelled on the Hohokam occupation at Casa Grande.

Prior to the establishment of the Casa Grande Reservation in 1892, pioneering anthropologists provided the first interpretation of the prehistoric era. Partly from the early anthropologists' ideas, and partly from excavations and his own thoughts, Frank Pinkley established an interpretive story that remained the basis for explaining the prehistoric peoples from 1918 to the early 1960s. At the monument the mediums used to tell this story have been ranger talks, guided tours, self-guiding trails, museum displays, pamphlets, and books.

The first interpretation of the prehistoric Hohokam culture to be based on more than speculation developed in the 1880s. At that time two newly created archeological research societies (Archaeological Institute of America and the Smithsonian-affiliated Bureau of American Ethnology which was known as the Bureau of Ethnology after 1894) studied the Casa Grande and incorporated it as part of a larger debate about the prehistory of the Southwest. Consequently, two different interpretations about the use of the Great House developed. Adolf Bandelier, who worked for the Archaeological Institute of America, at first believed that the Casa Grande served as living quarters, but by 1892 he changed his mind and wrote that it was a fort. This view was later adopted by Frank Pinkley for his interpretation program even though his early explanations were influenced by J. Walter Fewkes of the Bureau of Ethnology who excavated at the Casa Grande reservation during the winters of 1906-07 and 1907-08. The Bureau of American Ethnology's position on Casa Grande came from F. H. Cushing who had led the Hemenway Expedition in the late 1880s. Cushing believed that the prehistoric culture that had occupied the Gila and Salt River valleys was a society composed of many classes and led by priests. He decided that the Great House had been occupied by the priest class and served as a temple. The lower rooms in the Casa Grande had been used to store tithed grain. After his excavations in 1906-07 Fewkes modified that viewpoint somewhat. At that time he wrote that the Gila Valley and its tributaries had been inhabited by an agricultural people who were ruled by a chief. These people built great houses which served as places of refuge, ceremony, and trade. In time, hostile migrants came from the east for pillage and drove the agriculturalists from their villages. Some of the inhabitants moved south to Mexico, others went north to the Verde Valley and Tonto areas, while a few people remained in the Gila River region and became the ancestors of the present day Pima and Papago. [1]

Pinkley accepted Fewkes' interpretation at first and placed an extract of it in a 1909 General Land Office publication. He noted that the structures with massive walls had served as temples, granaries for corn storage, and forts for protection against foes. The common people, he wrote, lived in rectangular-shaped dwellings whose upright log walls were covered with mud or clay. [2]

By 1918, when Pinkley returned to Casa Grande for his second custodianship, he had developed the basic National Park Service interpretive theme which would be presented to the monument visitors until 1964. Pinkley reasoned that the prehistoric people did not come from a long migration to the area. They could have come from as little as 150 miles away. He adopted the traditional hunter! gatherer story to explain the prehistoric people's early appearance in the area. In developing that story, Pinkley told visitors that these people did not settle along the Gila River at first, but sought a home in the mountainous areas of central Arizona. Since these higher elevations prevented agriculture, the people lived as hunters who followed game from one mountain range to another. Pinkley reasoned that hunting and gathering did not provide adequate food, so gradually these people left the nomadic life and settled in the flat valleys where they experimented with agriculture and irrigation. Pinkley saw an ever upward progression of their culture because the development of an agricultural society led these prehistoric people to produce enough food and to live in better houses. [3]

Pinkley wrote that the first valley settlements were close to the Gila River since the early irrigation ditches did not extend far. Archeological evidence showed Pinkley that early houses consisted of crude reed-and-brush-covered structures and also demonstrated that these people developed more complicated dwellings. The change in house design led Pinkley to decide that someone of the prehistoric group eventually put mud on the brush to keep out the wind and this experiment resulted in the discovery that mud made the house cooker in the summer and warmer in the winter. Consequently, Pinkley thought, the people tried to make the mud walls thicker, but mud applied to brush could not be made more than three to four inches wide without collapsing. Archeological evidence revealed to Pinkley that, about AD 700, a new development in wall construction occurred when three-inch or more diameter timbers were used as core rods to make mud walls up to ten inches thick. This development, Pinkley thought, resulted from experiments. [4]

Pinkley told visitors that the prehistoric inhabitants of Casa Grande originally lived in peace, but, in time, other Indians moved into the mountainous areas and became a source of trouble for the agricultural people by raiding their crops in poor hunting years. Other than a preconceived picture of native populations, Pinkley had no evidence for raids. He merely used ideas developed by Bandelier and supposedly confirmed by Fewkes' excavations that this prehistoric society lived in a fort. No one ever thought to explain the need for walled villages in any other terms than for a defense system. The walled fortress idea led naturally into the next conclusion that people would also want to see the approach of an enemy. That idea, of course, led Fewkes to the watch tower conclusion which was an easy way to explain the pyramidal mounds topped with houses that he uncovered in Compound B. This was followed by the great house concept as the ultimate watchtower. Pinkley decided that, through experiments, the prehistoric people discovered that walls could be made taller without pole supports by making them thicker. Consequently, the National Park Service story stated that at first a great house was three stories tall, but soon other buildings had a fourth story to make it possible to see an enemy at a greater distance. The wall construction techniques for these taller structures came from observations that the walls were laid by hand in two-foot courses without forms. Since the ground floors of the four-story buildings were filled with dirt, Pinkley could think of no other explanation than it was necessary to absorb wall strain. Believing that no one would waste space, Pinkley decided that, in addition to functioning as watch towers, these great houses served as living quarters. He also thought of the buildings as a final line of defense. How else to explain the small doorways other than to force an enemy to come through the entrance one at a time in a stooped angle. Pinkley would explain to visitors that, in this defenseless position, it was easier for the defenders to hit an attacker over the head. To add to the defense story, Pinkley decided that a parapet on the roof allowed defenders to stand or kneel behind it. [5]

Pinkley concluded that, at their most prosperous period, the prehistoric people probably numbered between 8,000 and 15,000 in both the Gila and Salt River valleys. The trash remains and irrigation canals told Pinkley that these people farmed extensively and raised cotton and corn. Archeological excavations unearthed implements which provided display items. Fewkes, Pinkley, and others found that these city dwellers used stone, wood, and bone for tools and brought shells from the seashore for decorations and ceremonies. By making excavations of his own, Pinkley decided that the elliptically shaped depression between Compounds A and B was not a reservoir, as Fewkes thought, but an open air gathering place for ceremonies or games. Pinkley thought that it was used twice each year for ceremonies to pray for a good crop and to thank the gods for the harvest. [6]

Although Pinkley did not know when the Apache migrated to the southern Arizona area, he speculated that it was probably these people who joined the mountain inhabitants and gradually pushed the valley dwellers from their homes. The Apache, Pinkley thought, were not interested in agriculture and would have burned the villages. This view explained to him the reason for the burned rafters and roofing material found in excavated rooms. At a later date, Pinkley believed, the Pima and Papago came into the area, but they were not advanced enough to restore and use the villages. [7]

Pinkley added to his interpretation of the Casa Grande occupation after Harold Gladwin made several excavations in the monument during February and March 1927. Gladwin, an archeologist with the Southwest Museum in Los Angeles, cut through several rubbish mounds to examine the layers of trash placed there over time. In this manner he hoped to find the changes that had occurred in the prehistoric society. Gladwin could not trace the identity of these prehistoric people to any existing society. He was certain that the Pima culture had no similarity to the ancient Casa Grande occupants. Unable to provide an identity for this culture, Gladwin accepted the Pima name "Hohokam." Consequently, the term Hohokam came into common usage both in the interpretive program and among archeologists. [8]

Gladwin felt that too much emphasis had been placed on the use of compound walls and the Great House for defense. Since the Casa Grande museum building had been destroyed by a flood only two years before Gladwin arrived, he decided that the compound walls had served for flood protection. In addition, the Great House had been built for storage protection from floods which, he thought, explained the reason why the prehistoric people had filled the ground floor with earth. [9]

Pinkley did not accept Gladwin's flood idea. He continued to emphasize the defense interpretation. At the same time, Pinkley did adopt another of Gladwin's conclusions. After slicing through several rubbish mounds, Gladwin noted that the lower, thicker layers of trash contained pieces of traditional Hohokam pottery. He described this earthenware as red-on-buff. Previously, it had been called either "old red ware" or red-on-gray. The narrow top layer, however, included pieces of a different pottery. This polychrome pottery was similar to that manufactured by the Salado, a puebloan people who lived to the northeast of the Hohokam territory. As a result, Gladwin decided that, in the last period of Hohokam occupation, the Salado had migrated to the Gila Valley and lived peacefully with them. He believed that not only the change in pottery proved the theory, but the change in building style to multi-storied structures showed the pueblo influence. Additionally, Gladwin found a change in burial customs which only further confirmed his belief in a Salado migration. The traditional burial practice of the Hohokam had been cremation with the ashes placed in red or red-on-buff pottery. Gladwin, however, discovered skeletal remains which had not been cremated. These remains were only found with the Salado polychrome pottery. He concluded, therefore, that the Salado had influenced the Hohokam to change from cremation to inhumation. [10]

Red-On-Buff Hohokam 12th Century, Pottery.

Within a year after Pinkley's death in 1940, a slight interpretive change was made. Visitors were told that the Hohokam had migrated to southern Arizona from northern Mexico. Monument personnel stated that the greatest range of Hohokam culture came about AD 1000 when it extended from the Flagstaff area to the Mexican border and from New Mexico to present-day Gila Bend. Over the next several hundred years, their territory shrank and people settled in compact villages surrounded by high walls for protection from an enemy. Park Service speculation now made the foe a Yuman group from the lower Gila and Colorado rivers instead of the Apache and mountain people because it was now known that the Apache had arrived in southern Arizona at a later date. Rangers repeated Gladwin's idea that, about AD 1300, the Salado, who dwelled on the upper reaches of the Salt River, were pushed into the desert by drought. They migrated to the Hohokam settlements where, as Gladwin thought his excavations showed, they influenced that culture as seen by the construction of multi-story buildings, the manufacture of polychrome pottery, and a new burial practice. National Park Service archeologists accepted Gladwin's theory because it made a good story to explain the appearance of the great house style architecture. No one thought to carry through with Pinkley's earlier idea that architectural change had come about through experiment. Visitors learned that shortly after 1400 the union ended and both the Hohokam and Salado abandoned the Gila River villages. Since most events are usually said to result from complex causes, the National Park Service story included other incidents to explain the end of the prehistoric culture. No longer were people told that the Hohokam and Salado departed their homes only because of attacks from hostile neighbors. Rangers provided a series of other factors which included the possibility that the soil had become waterlogged through years of irrigation, that silt had filled canals, and that, in all likelihood, a drought had occurred. Unlike Pinkley's idea, at least in part, the Hohokam were thought to have remained in the area to become the ancestors of the Pima. [11]

Only one variation in this interpretive story occurred during the 1950s. In 1952 Albert Schroeder claimed that the people who migrated to live with the Hohokam were not Salado, but the Sinagua who had resided to the north in the present-day Flagstaff area. Consequently, neither the name Salado nor Sinagua was used in reference to these people. They were termed people of pueblo origin. [12]

The entire interpretive story changed in 1964. When Charlie Steen excavated a small, previously undisturbed area in Compound A in 1963, he found evidence that Casa Grande had always been occupied by only the Hohokam. Steen wrote that, prior to that time, he had firmly believed in the "Salado-in-the-desert" idea. From the time of Gladwin's excavations in 1927, Compound A was considered the product of Salado construction because of its architectural style and the time in which it was built (soon after 1300). Under that circumstance, Steen should have found mostly pieces of Salado polychrome pottery. Instead, the pot shards he located were either Hohokam Gila Plain or red-on-buff. The few pieces of polychrome that he found had to be obtained from trade. Subsequent excavation at Hohokam sites by such archeologists as David Doyel of the Arizona State Museum have shown that there was no migration of Salado or any other people to the Hohokam villages. Gladwin had come to the wrong conclusion. The development of multi-story caliche buildings resulted from a transition in Hohokam building techniques. As a result of this new evidence, the interpretation of the Hohokam civilization changed to that presented in the first chapter of this study. [13]

Another subject interpreted at Casa Grande involved the use of the Great House for astronomical purposes. Sometime during his first custodianship, Frank Pinkley noticed that there was a system of holes in the east wall of the Great House through which the rising sun aligned each year on the mornings of March 7 and October 7. By 1918, without any study or investigation, he explained to visitors that these holes were used twice each year as a solar calendar to date ceremonies. In 1920 Pinkley broadened his astronomical interpretation after he discovered holes in the Great House's north wall. He invented an elaborate initiation ceremony story, which involved "calling down the stars," to explain these holes. Pinkley told visitors that, to impress the tribal youth during initiation, priests would get them to peer through these northward facing holes at night. On the opposite side of the wall a priest would hold a bowl of water that reflected star light. In the dark that reflected light would appear as if the priest had called down the stars to earth. [14]

Although it was later discovered that the north wall "astronomical holes" had been drilled during the 1891 preservation work, studies of the east wall holes, beginning in 1969, supported their use for solar observations. Prior to that date Southwestern Monument and Casa Grande employees merely observed the sun's alignment in the spring and fall and wrote articles to publicize this solar phenomenon. No comparative studies were made with either contemporary societies or historic groups to learn of their astronomical practices. It was only assumed that the Great House holes were used as a solar calendar. Wishing to have the holes studied, the Southwestern Archeological Center contracted with John Molloy in 1969 to investigate the Great House holes. He identified fourteen holes that he felt were used to make lunar and solar observations. This development of astronomy at Casa Grande, Molloy thought, had come from Mesoamerican influence. In 1971 his report was accepted with reservations because he had merely described the holes and their lunar and solar orientation. Molloy did not list any importance for the holes or state any reason for their astronomical use. Another contract was issued to John Evans in 1978 for further study of the holes. He found that two holes on the east wall had a solar alignment with the spring and fall equinoxes while one hole on the west wall aligned with the setting sun at the summer solstice. Soon after Evans began his investigation, Renee Opperman conducted her own observations. She made a comparative study of rituals in relation to astronomical developments in both prehistoric and historic Native American cultures. On the basis of similar astronomical uses in both North and Mesoamerica, Opperman concluded that, because of the Great House orientation along with the equinox and solstice holes in its east and west walls, the inhabitants of Casa Grande depended upon the heavens "as a source of life or of signs that aided in sustaining life." [15]

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Last Updated: 22-Jan-2002