From the Introduction:
The Hopi Indian people live in a series of pueblo villages in the high mesa country of northeastern Arizona. Although this region is rugged and arid, the Hopi people have lived here for centuries-traditionally subsisting on such staples as corn, beans, and squash. Farming on this land requires great skill and an intimate understanding of the characteristics of the environment, for such forces as frost, hail, flash floods, high winds, and drought often combine to threaten crops.
The traditional religious system of the Hopi reflects their dependence upon and sensitivity to the precarious nature of this agriculture. Over the years, the Hopi have developed a set of annual ceremonies that emphasize the fertility, germination, growth, and maturity of their crops. All of these ceremonies, which are conducted by a number of ceremonial groups or societies, focus on the everpresent need for rain. Most of these groups have an exclusive membership. However, one group includes any willing initiated member of the Hopi tribe, and it is the male members of this group (along with the members of the more exclusive Powamuy Society) that perform the most visible and pervasive of the Hopi ceremonials-those of the kachina cult. (Note: the word kachina is linguistically more correct if spelled katsina or, if plural, katsinam. )
The kachina ceremonies reflect the traditional Hopi view of their universe. A fundamental theme of their world view is that the universe is divided into two realms: the upper world of the living and the lower world of spirits. Events occur between these two worlds in alternating and regular cycles. For example, the sun moves between the upper world by day and the lower world by night on its daily course. Likewise, it follows an alternating cycle through the year. As the days grow longer between the winter and summer solstices, the sun's energies bring germination and growth to the upper world.