This period can generally be considered a time of both growth and sexual change. The community of Snaketown, once central to the culture, was suddenly abandoned. It seems that parts of this large village were burned, and thereafter it was never reoccupied. This period also witnessed the construction of large and prestigious structures in the Salt-Gila Basin. These included large rectangular adobe-walled compounds with platform mounds and Great Houses, such as the example found at the Casa Grande Ruins National Monument.
• Santan Phase (AD 1050-1150)
This phase was initially proposed as part of the Gladwinian scheme, but recently has fallen out of favour with many Hohokam archaeologists. The primary reason for this view is that the Hohokam Buff Ware type once classified as Santan Red-on-buff is now listed as either a late form of Sacaton or Casa Grande red-on-buffs. The wide range of vessel forms used for decorated pottery was discarded for globular jars with necks, while overall there was a significant decrease in production and use of Hohokam Buff wares. There also was a radical decline in the procurement and trade of raw shell from northern Mexico and its manufacture into jewellery. Another trait of this phase was the transition from pithouses to pitrooms and the introduction of spherical spindle whorls similar to examples used in northern Mexico.
• Soho Phase (AD 1050/1150-1300)
The ceramic type for this phase was Casa Grande Red-on-buff. This Hohokam Buff Ware was characterized exclusively by jars with necks, decorated with a limited variety of geometric and textual designs. This pottery type appears to have been manufactured in the Gila River basin between Florence and Sacaton, Arizona. There were major cultural retraction in terms of territory and two significant episodes of reorganization in this phase.
The first reorganization occurred around AD 1150. There was a modest increase in population and near universal adoption of pitroom architecture. These early pitrooms were built of perishable material covered with a thick adobe plaster, and the base of the interior walls was often lined with upright slabs. Similar to the Pre-classic Period villages these early Classic Period habitation structures were clustered around open courtyards. These courtyard groups were then clustered near a large central locus, which often included small platform mounds. These platform mounds were rectangular, faced by post-reinforced adobe walls, and were filled with either sterile soil or refuse from Pre-classic trash mounds. In the largest villages the central locus included small platform mounds. The number of small and medium-sized settlements seems to have declined as the larger communities became increasingly more densely occupied.
• Civano Phase (AD 1300-1350/1375)
Although Casa Grande Red-on-buff continued to be produced, the pottery type that characterized this phase was Salado Polychrome, primarily Gila Polychrome. This ceramic type was either manufactured locally or procured as a trade ware. This phase also saw the production of bird-shaped effigy vessels. Examples of exotic stone and shell artefacts associated with high-status individuals such as nose plugs, pendants, ear rings, bracelets, necklaces, and sophisticated shell inlays, indicate that the design and manufacture of jewellery reached its zenith during this phase. Other important developments were the significant increased procurement and manufacture of Red ware, and the near universal use of inhumation burial in the area north of the Gila River, both similar to the practices and traditions utilized by the historic O’odham.
After AD 1300, Hohokam villages were reorganized along the lines experienced in the Lower Verde, Tonto Basin, and Safford Basin, in the 13th century. A large rectangular exterior wall, either completely or partially, enclosed a series of contiguous courtyards and plazas delineated by interior partition walls. Each courtyard may contain one to as many as four large rectangular adobe-walled pitrooms. These communities were clusters of between five and 25 adobe-walled compounds, grouped around a single very large and well built compound or large community structure, such as a platform mound or Great House. Great House structures, as with the one preserved at Casa Grande Ruins National Monument, were built only at the largest communities. These stone or adobe buildings had up to four stories, and were probably used by the managerial or religious elites. They may have also been constructed to align with astronomical observations. Trade with Mexico appears to have declined, but an increased number of trade goods arrived from Pueblo peoples in the north and the east.
Between AD 1350 and 1375, the Hohokam tradition lost vitality, stability, and many of the largest settlements were abandoned. Rapidly changing climatic conditions impacted the Hohokam agricultural base and prevented the cohesion of their large communities. Repeated floods in the middle 14th century reduced the Salt River bed while destroying canal heads. Flooding rendered hundreds of miles of canals virtually useless. Because of its hydrology and geomorphology, these processes had a lesser impact on the irrigation systems used by the Hohokam in the Gila River basin, yet these were abandoned as well.
• Polvoron Phase (AD 1350/1375-1450)
This phase is characterized by the widespread use and manufacture of Salado Polychrome, with both Gila and Tonto polychromes. After AD 1375, the Hohokam abandoned the villages and canal systems within the lower Salt River basin. However this area continued to be occupied, albeit on a far smaller scale. Meanwhile, the very few villages that remained were quite small and concentrated along the Gila River, with the exception of the lower Queen Creek drainage. This episode is relevant and of great historic importance as it represents the immediate aftermath of the Hohokam cultural collapse and in part signifies a critical stage in the ethnogenesis of the modern O’odham.
