Peoples of the Inland Sea. David Andrew Nichols

Native Americans to continue increasing their numbers after their old nomadic hunting economy became unsustainable. By 1000 BCE there were probably around one million people living in North America north of the Rio Grande. If the human population in the Great Lakes region maintained its proportion to the overall Native North American population, then it reached approximately fifty thousand people by the end of the Archaic era.⁸

      The Archaic era ended with the rise of several sophisticated cultures in the upper Ohio River valley: the Adena culture (1000–100 BCE), the Hopewell cultural system (200 BCE–500 CE), the Mississippians (900–1500 CE), and the Fort Ancient culture (1000–1500 CE). The Adena people, named for the “type site” in Ohio where archaeologists first discovered their artifacts, had a social or religious elite whom they interred in wooden tombs covered by conical earthen mounds. With their former leaders they buried ceremonial goods like carved stone pipes and figurines of people or animals. The culture occupied a region extending from southern Indiana to West Virginia and from central Ohio to central Kentucky. Most of its people lived near the Ohio River and its tributaries, where large populations of fish, game, and wild plants provided enough food to support dense human populations—more than ten times as many people per square mile than in the uplands.⁹

      The Adena people’s successors, the Hopewellians, covered a much larger geographical area; they were a network of societies bound together by trade and some common cultural forms. The main Hopewell peoples resided in central Ohio and northern Kentucky, while their cultural relations and trading partners dwelt in Michigan, Indiana, Illinois, and Wisconsin. The Hopewell people lived in widely separated homesteads in river valleys and, like their Adena predecessors, spent part of their labor building large burial mounds for their elite. Hopewell mounds usually formed geometric shapes, and their builders sited them near other earthen buildings in ceremonial complexes, some of which covered several square miles. At the edge of these complexes, the Hopewellians built temporary dwellings where commoners lived part of the year, while they were constructing earthworks or attending religious ceremonies, before they returned home to hunt and plant.¹⁰

      In their mounds, the Hopewellians interred not only their leaders but also hundreds of grave goods, many of which they fashioned from exotic materials: obsidian blades, copper jewelry, mica cutouts of human hands, and artifacts made of marine shells and grizzly-bear teeth. The trade network that provided these materials extended south to the Gulf of Mexico and west to the Rockies. The goods themselves were most likely “prestige goods,” indicators of status that circulated in a different economic sphere from ordinary goods like food or animal skins.¹¹

      It is not easy to draw conclusions about the nonmaterial lives of Hopewell peoples from the remains they left, but the anthropologist Matthew Coon has made some thought-provoking suggestions. The orientation of human remains at one Hopewell-era site in Ohio, he argues, indicates that the Indians there may have organized themselves into social “halves” (or “moieties”). Such large binary groups would have helped draw potentially rival families and clans together. Coon also believes that some of the Ohio Hopewellians’ engravings show human beings wearing animal masks, and he notes that masks would have improved social harmony by allowing lower-ranking people to disguise themselves while they publicly criticized their ruling elite. His hypotheses help answer one of the most fundamental questions facing any large society with a governing class: why do the governed give their allegiance to the governors? In the case of some of the Hopewell communities, the answer may lie in the formation of large groups that increased social solidarity and in the development of mechanisms for criticizing rulers.¹²

      The Hopewell era coincided with the spread of a new crop, Mesoamerican maize (Indian corn), through the Ohio valley. It is likely that maize agriculture led to population growth in the region. A carbohydrate-rich diet lowers the risk that pregnant women will have miscarriages, and the development in the fifth century CE of thinner pottery that one could use to heat food more efficiently allowed women to turn maize into gruel, which they could use to wean their children at an earlier age. Women who stopped lactating would then resume their menses and their fertility. Population growth, which provided the labor force for the Hopewellians’ mounds and earthworks, may have eventually produced social conflicts and stresses that the Hopewell culture’s institutions could not contain. Perhaps this helps explain that culture’s disappearance after 500 CE. Only a few centuries would pass, however, before new “mound-builder” cultures would take Hopewell’s place.¹³

      One of these cultures, the effigy mound builders of modern Wisconsin, emerged during the Late Woodland period (500–1200 CE) and began building their distinctive mounds around 700 CE. The Wisconsin mound builders lived in an ecologically diverse region rich in food resources: forests harboring game animals, marshes full of fish and birds, and flat prairies suitable for raising corn, which local Indians adopted around 900. They constructed their mounds, numbering over three thousand by 1200 CE, at places where large numbers of people gathered to hunt, fish, and hold religious ceremonies. The mounds themselves apparently formed a vast symbolic map of the effigy builders’ cosmology. Some of the effigies, concentrated in southeastern Wisconsin, represented long-tailed water spirits from the builders’ watery underworld, similar to the manitous in the Odawas’ creation and flood story. Some, concentrated in southwestern Wisconsin, represented bird spirits from the builders’ Upper World, akin to the thunderbirds from Ojibwa mythology. Some, located in a band across the present southern border of Wisconsin, represented bear and other animal spirits from the Middle World (that is, the physical world). A few represent a horned human who may have been a precursor of Red Horn, a culture hero of the Ho-Chunks, whose cosmology resembled that of the effigy builders. The finished mounds were probably ceremonial centers—some contain concentrations of stones that archaeologists believe are the remains of altars—and they certainly served as burial mounds, though the sparseness of grave goods suggests that the effigy builders had an egalitarian society, certainly more so than their Mississippian neighbors.¹⁴

      The Mississippians would become the most famous of the post-Hopewell mound-building cultures. Their society arose around 900 CE and flourished in the greater Mississippi valley and the southeast until 1500 CE. The Mississippian people practiced intensive agriculture, lived in large towns or cities, built large temple mounds, and organized themselves into a hierarchy of social classes. Of the urban centers that the Mississippians constructed, the largest was Cahokia, a city built on the bottom lands near present-day Saint Louis. Cahokia’s establishment was more a revolutionary than an evolutionary event: its builders erected much of the city in a single surge of construction that began around 1050 CE. Archaeologist Timothy Pauketat speculates that the Cahokians may have drawn inspiration from the Crab Nebula supernova of 1054, which produced a bright new star visible everywhere in the world. Cahokia was centered on a massive, terraced platform mound, known today as Monk’s Mound, which stands over one hundred feet high and is comparable in size to the stone pyramids of Mesoamerica. The city featured several other platform temple mounds, a vast public plaza, several wooden “henge” structures used as astronomical calendars, and the dwellings of about fifteen thousand residents. No other city north of Mexico would reach this size again until the 1700s.¹⁵

      The Mississippians’ hierarchy comprised a small elite of priests and nobles, a large class of commoners and warriors, and a population of slaves at the bottom. Mississippian slaves were generally war captives, and like slaves elsewhere in the world they were (to borrow sociologist Orlando Patterson’s term) “socially dead,” not part of any kin group or patron-client relationship. Slaves at Cahokia sometimes became more permanently dead: archaeological excavation of one of Cahokia’s mounds uncovered the remains of more than eighty men and women killed at the same time and interred with two high-status men. The eighty victims were almost certainly slaves sacrificed to “accompany” the two priests or nobles into the grave.¹⁶

      Life in Cahokia was marginally better for commoners, but even they suffered from dietary deficiencies and hard labor, which raises the question of why they would remain in Cahokia and other Mississippian settlements if life was so difficult. Some Mississippians, like the nearby farming villagers who provided Cahokia’s food supply, may have feared attack or enslavement if they didn’t move into the region. Others probably remained in Cahokia and other Mississippian towns for security: there was safety in numbers,