In the study of the Hopi religious rituals and festivities, Fewkes compiled descriptions and drawings of the Hopi Katsinam. He also commissioned several Hopi artists, knowledgeable in the Katsina cult and with the least outside influence in their work, to produce a series of paintings of these supernatural beings of the Hopi, the Katsinam. The resulting Codex Hopi, a manuscript of all the known Hopi Katsinam, was the first permanent documentation of the ceremonial performers. It documented and preserved the Katsinam, who may otherwise have ceased to appear.
