Mound builders were early groups of Native Americans who built large earthwork structures. They built more than 5,000 mounds throughout North America between 7000 B.C. and A.D. 1700. Most mounds are in the eastern regions of the United States, with the greatest number around the Mississippi and Ohio rivers. Mounds are also found throughout eastern Canada and the southeastern United States.
Mounds in North America occur as single structures or in groups and in a variety of shapes and sizes. Some mounds were used to bury the dead. Others provided foundations for houses and temples or served to identify or mark the territories of different groups.
During the 1800’s, some scholars thought that the mounds were remains of an ancient civilization. They theorized that the ancient mound builders came to North America from Europe, from Egypt, or even from the legendary continent of Atlantis. However, by 1894, archaeologists from the Smithsonian Institution had excavated several mounds and proved that the mound builders had been the ancestors of modern Native Americans.
The mound builders were not a single group of people. Instead, different Native American cultures built the mounds over thousands of years. The mounds were entirely built by people transporting and depositing loads of soil and rocks by hand without the use of wheeled vehicles or draft (work) animals, such as horses or oxen. Archaeologists recognize three broad prehistoric periods in which mound building occurred in North America. They are the Archaic Period (7000 B.C. to 1000 B.C.), the Woodland Period (1000 B.C. to A.D. 1100), and the Mississippian Period (A.D. 900 to A.D. 1700).
Archaic Period.
Native Americans of the Archaic Period lived in small, seasonally occupied camps, and survived by hunting, fishing, and gathering wild plants. In some areas, however, a few groups began to cultivate sunflowers, gourds, and other plants. They made tools of chipped stone. They also manufactured various items from bone, hides, and other animal products; and wood and other plant materials. By the end of the Archaic Period, some groups had begun to make and use pottery.
The earliest evidence of Archaic Period mound building is at a site called L’Anse Amour, near Forteau, on the Labrador Peninsula, Canada. There, Archaic Period people built a circular pile of boulders in about 5500 B.C. to mark the grave of a child. By 3,000 B.C., Archaic peoples were building low, circular burial mounds throughout the Mississippi Valley and nearby areas.
A site called Poverty Point, near Epps, Louisiana, preserves some of the most unique mounds of the Archaic Period. Archaeologists believe that this site was an important center for trade among Native American groups in the region. Archaic people built a large group of mounds there between about 1800 B.C. and 500 B.C. The mound complex is composed of six semicircular earthen ridges, each more than 1/2 mile (0.8 kilometer) in diameter. The ridges were about 80 feet (24 meters) wide and nearly 10 feet (3 meters) high. The ridges surround two large mounds up to 65 feet (20 meters) in height. Many smaller mounds stand nearby. Archaeologists believe that the mounds were built as foundations for houses that stood on top.
Woodland Period.
Many early Woodland peoples moved seasonally to hunt, fish, and harvest wild plants, as their Archaic ancestors had done. Over time, Woodland groups became more reliant on cultivated plants and settled into small communities. The communities grew gourds, squash, sunflowers, and other food crops, and tobacco. Maize (corn) became an important crop during the later Woodland Period. The Woodland Period is also characterized by widespread use of pottery and mound building. Many Woodland mounds were cone-shaped. Some were as high as 30 feet (9 meters).
Archaeologists recognize two major mound-building cultures of the Woodland Period, the Adena and Hopewell. People of the Adena culture built many large mounds beginning about 600 B.C., centered in what is now southern Ohio. Over time, the Adena culture gave way to the more widespread and complex Hopewell culture, which flourished from about 100 B.C. to about A.D. 500. It extended throughout present-day Ohio, Indiana, Michigan, Illinois, Wisconsin, Iowa, and Missouri.
Adena and Hopewell mounds usually contained one or more burials, often accompanied with finely made pottery and objects fashioned from imported materials. Hopewell traders obtained shells and shark teeth from what is now Florida and pipestone, a soft stone used to make pipes, from present-day Minnesota. They also traded for obsidian (volcanic glass) from the Wyoming area and silver from what is now Ontario. Archaeologists believe that the people buried in the mounds were high-ranking members of the society.
The Hopewell trade network collapsed by about A.D. 500, and mound building ended throughout much of the region. However, some regional mound-building traditions emerged toward the end of the Hopewell culture. Prehistoric groups in what are now Iowa, Minnesota, and Wisconsin built many effigy mounds in the shape of birds and other animal forms. Other Woodland societies began settling in more permanent villages and gave rise to the cultures of the Mississippian Period.
Mississippian Period.
Mississippian communities became established in the river valleys across what is now the southeastern United States after A.D. 900. Mississippian people raised livestock and grew crops. They built some of the earliest towns and cities of North America. The larger towns often centered around mounds and other earthworks bordering a plaza where public events took place. The mounds ranged from 10 feet (3 meters) to 40 feet (12 meters) in height. Many Mississippian mounds were pyramid-shaped with flat tops, though the Mississippian builders also erected cone-shaped and linear mounds. Archaeologists believe that temples stood on top of the mounds along with buildings for the ruling chiefs. Stockades (log walls) protected many towns, indicating that warfare was common.
The largest Mississippian city was Cahokia, in present-day Illinois. Archaeologists estimate that it had a population of between 10,000 and 20,000 residents. Monks Mound, the largest mound in Cahokia, rises about 100 feet (30 meters) and covers about 16 acres (6 hectares). Cahokia had more than 100 other mounds. Many were burial mounds, and others served as foundations for temples or for the houses of city officials.
Mississippian people made varieties of decorative pottery, much of it in the shapes of animals and human beings. Stone pipes in the form of human figures and crafts of imported shell and copper are also found at many Mississippian sites. The imported materials are evidence that Mississippian people traded with other groups through an exchange network that extended over much of eastern North America.
In what is now Ohio, people known as the Fort Ancient culture built mounds, earthen forts, and other structures. These people were culturally distinct from other Mississippian Period communities to the west. The name of the culture comes from one of their largest forts, Fort Ancient, near Lebanon, Ohio. A famous mound built by the Fort Ancient people is the Great Serpent Mound, near Hillsboro, Ohio. It looks like a huge snake from the air and is about 1/4 mile (0.4 kilometer) long. The mound’s purpose is unknown.
Conflicts with the Europeans and diseases introduced by them led to the destruction of Mississippian culture and brought an end to the mound-building traditions in the early 1700’s. Since then, construction and land clearing have destroyed many mounds. Some states now have laws to protect mounds.
See also Effigy Mounds National Monument; Ohio (Places to visit).
