a smaller scale and took advantage of a much larger variety of the ecology of the region.24 In contrast to the complexity of Cahokians, they were “simple” and regularly relocated villages to take advantage of different aspects of the local ecology.
Although we cannot be precise about details, archaeological evidence suggests that the Oneota newcomers were factionalized and organized into small social units.25 They also lived a rather Hobbesian existence, since violence was endemic in the Illinois after Cahokia’s decline. Archaeological sites from the 1300s and 1400s in the Illinois Valley reveal fortified villages and other evidence of warfare between Oneota and Middle Mississippian groups. Perhaps the most dramatic evidence of violent lifeways in this period is an Oneota village, dated to the year 1300, in the central Illinois Valley. The site contains a cemetery with 264 burials. Sixty-six percent of the people interred at the cemetery had been decapitated or scalped at death.26 Life was hard in the wake of Cahokia.
In addition to warfare, other factors kept the population of the Oneota villagers low. Continuing the trend of the Pacific event that started in the 1200s, another climate episode began in the 1400s: the Little Ice Age. While this created well-known disturbances around the world and especially in Eurasia, it also brought about a significant shift on the North American continent.27 By some estimates, the Little Ice Age may have reduced the average summer temperatures by 1.5 degrees Celsius in mid-America.28 The temperature shifts may have produced as many as thirty-four fewer frost-free days in the modern state of Illinois. The continuing low human population in the vacant quarter that this and previous climate events helped occasion may be responsible for producing a rather sudden and dramatic species shift in the region. With few people in the Illinois Valley, and thus so few potential hunters, the population of wild animals may well have spiked.29 By the 1500s, the great wild ungulates of North America, bison, had invaded the grasslands east of the Mississippi River in large herds, probably extending the prairies with their grazing as they advanced.30 They came in great numbers, congregating by salt licks and springs, such as near Starved Rock in the Illinois Valley.31
There is an important reason why bison revolutionized lifeways for the Oneota occupants of the midwestern prairies. As is well-known, tallgrass prairies in the middle of the country sat atop the thickest topsoil layer anywhere in the world.32 Yet the dense root systems under the grass made it impossible to farm these soils until the invention of steel plows in the nineteenth century. Native Americans did not have plows or metal farming tools of any kind, and so they normally did not exploit the prairies as farmland. Instead, they used hoes to farm the fertile soils of the bottomlands. Meanwhile, although game species like deer and elk could be found in the tallgrass prairies, they were most commonly located at the “edges” where grasslands and forests overlapped. Remarkable evidence of prehistoric trash pits suggests that prairie environments were largely underutilized. In one Huber phase Oneota trash pit from the 1400s, for instance, only 2.4 percent of the animals used by the residents came from the prairie, while the vast majority came from the valley floors, forests, and wetlands.33 This was probably typical. For much of the prehistoric period, it seems clear that the prairie itself probably went relatively unused by human inhabitants of the region.34
This is important because prairie made up close to 55 percent of the land in the modern state of Illinois, even more in the modern state of Iowa. Since they could not easily exploit this land for farming, and since their preferred game did not usually congregate in prairies but on its edges, this meant that the Native inhabitants of these regions left prairies as a largely untapped ecosystem. Here were calories, produced by grasses, which the Oneota villages had little means to exploit. Humans, of course, could not eat the grasses, nor could they easily replace them with edible plants.
The large-scale invasion of the bison into midwestern grasslands from points west thus created a great new subsistence opportunity for people whose climate was changing, and particularly for farmers whose calorie yield was compromised by both rainfall shortages and possible flooding. Newly arriving bison of course could use the prairie grasses, eating them up to become what one historian calls “reservoirs of biomass.”35 In ecological terms, bison were able to convert the “vast energy stored in the … grasses for human use.”36 Deer and elk were certainly important before, but bison arrived in the region in huge herds and were relatively simple to hunt, provided one had a cooperative group to help direct the animals to a kill zone. Indeed, bison hunting produced calories on a totally different scale than deer hunting: each animal weighed 2,000 pounds, containing at least 675 pounds of useful meat. Hunts in the tallgrass prairies regularly yielded hundreds of animals at a time.37 For Oneota people accustomed to starchy agricultural diets, the new resource created a dramatic increase in nutritional quality, fairly quickly.38 The invasion of the bison brought tremendous change to Native life in Illinois between 1500 and 1800.
By turning the prairies from wasteland to productive, the arrival of bison vastly increased the amount of calorie-producing land in the future Illinois Country. The new animal resource was so attractive that it inspired migration among many of the inhabitants of the region. The eastern spread of bison pulled more Oneota people to the West, back out onto the prairie peninsula and closer to the plains environment, as they increasingly specialized in bison hunting.39 This “bison revolution” confirmed the Oneota’s status as a “bridging culture,” connected to the two biomes and lifeways of the woodlands and the plains.40
To be sure, not everyone went west. The so-called Huber phase Oneota sites remained in the northern part of the Illinois River Valley. These were prosperous places, now augmented and altered by bison exploitation. Trash pits at the Fisher site in the upper Illinois Valley from this period reflect a great deal of diversity in the diet of these Oneota people, who now added bison to an extensive list of flora and fauna that they exploited on a seasonal and cyclical basis.41 The survival and persistence of these Oneota culture groups in the wake of Cahokia set the stage for the protohistoric and historic transformations in Illinois.42
Meanwhile in the East, Algonquians living south of Lake Erie and in the Ohio Valley were also suffering from climate change that made agriculture difficult. As in the Illinois Valley, this produced violence and warfare, even what one archaeologist calls a period of “ethnic cleansing” as proto-Algonquian groups struggled to survive.43 Some Algonquians, concentrated in settlements just to the south of Lake Erie, interacted and shared pottery traditions with a group identified by archaeologists as the Fort Ancient people, who lived in modern-day southwestern Ohio.44 Pottery traditions and archaeological assemblages suggest that these proto-Anglonquian groups began to trade with Oneota peoples at the Huber phase sites in the upper Illinois Valley in the 1500s. Before long, they were in close contact with these Oneota groups, carrying prestige goods back and forth across the modern state of Indiana in a flourishing trade network.45 Interestingly, calumet pipes, the diplomatic tool of western Siouan-speakers, were some of the materials that Algonquians received from this new trade.46
But it was not just prestige goods and diplomatic symbols that passed back and forth between these Algonquians and their Oneota neighbors. Sometime in the 1500s, the Fort Ancient culture adopted another facet of the lifeway of their neighbors to the northwest: they started hunting bison. Limited numbers of bison had arrived in the Ohio Valley in the 1500s. There is no way to know whether the Fort Ancient hunters learned bison hunting from their Oneota trading partners, but it seems possible. Like their neighbors to the northeast, these Ohio Valley hunters experienced a bison revolution.47
It was probably bison that inspired the next important turning point in this story. In the late 1500s, a new pottery tradition known to archaeologists as Danner-Keating shows up in the Huber Phase sites in the upper Illinois Valley. Importantly, this Danner-Keating tradition strongly resembles pottery found in the Fort Ancient sites. Moreover, a very similar pottery tradition, which may be a root tradition for Danner,
