Traces of Hopewellian influence, possibly indicating inter-marriage with Hopewellians, have been noted at the Sugar Camp Hill site (date undetermined) in Jackson County, which is presumably later than Baumer. However, the Baumerians like the native Californians were conservative, for four centuries intervened between the oldest Hopewellian village in the north and the earliest known station of that culture in southern Illinois.[11] THE HOPEWELLIAN CIVILIZATION[12] (500 B.C.-500 A.D.) Toward the end of the Initial Woodland period maize or corn, as we call it today, was introduced into northern Illinois, presumably from Mexico and Middle America through the agency of intervening tribes. In an apparently short time, its production seems to have been greatly intensified and exploited. Other food crops and tobacco may have accompanied maize. About the same time, a formalized religion arose, probably concerned with the worship of deities who personified natural forces like the sun, rain and thunder, which were important to a plant-growing people. From the evidence of burial places, there seem to have been two or possibly three social classes. Doubtless the first comprised the families who introduced and grew the new food plants and who were inspired to invent the complex religion. The burial of the dead, especially those socially important and of the highest class, was accompanied by elaborate and colorful ceremonies closely bound to the religion. This seems to be a continuation in grander form of the earlier Red Ochre funeral and burial. It is unfortunate that we do not have tangible evidence of their other religious and political ceremonies which may have been even more impressive and significant. The official dress and insignia of the officials, which we can barely glimpse in the rich and varied remains in the tombs, signify a political system of social control and an established priesthood for the spiritual guidance of the community. Shamans or medicine men probably had only the duty of treating disease. Reverence for and possibly worship of ancestors is suggested by the impressive tomb chambers and mounds and the care obviously bestowed on certain of their socially prominent dead. Social and political prestige, religious pomp and ceremonial, all seem to have combined to stimulate a demand for rare materials, beautiful jewels and impressive regalia. This initiated the search for pearls at home, the development of skillful and artistic workmanship in flint, bone, shell, copper and mica, travel abroad and trade in materials obtainable only in distant regions.