Rich in both military and early Native American history, Fort Abraham Lincoln State Park is your destination!
Learn More at www.parkrec.nd.gov History


Fort Abraham Lincoln State Park in North Dakota is one of the outstanding historic areas within the state. The park is made historically important because within its boundaries are the ruins of On-A-Slant Mandan Indian Village and the Fort Abraham Lincoln cavalry and infantry posts.

The land itself was deeded to the state in 1907 by President Theodore Roosevelt. Park development started in 1934 by the Civilian Conservation Corps (CCC), who built the visitor center, earthlodges, blockhouses, shelters and roads, and placed cornerstones to mark buildings at the infantry and cavalry posts.

Additional development took place in the late 1980s and 1990s, with the reconstruction of the commanding officer's house, commissary storehouse, enlisted men's barracks and granary, all on the cavalry post grounds; and the Council Lodge in the On-A-Slant Village.

On-A-Slant Village On-A-Slant Indian village at Forth Abraham Lincoln State Park.
The history of the Heart River Mandan teaches that not all Plains Indians lived a nomadic life. Since most people equate Indian life on the Great Plains with that of the culturally different hunting and gathering Sioux, it may surprise some to know that the Mandan lived a sedentary, agriculturally-based society.
Newly studied archeological data suggests the On-A-Slant Village was established about 1575. On-A-Slant was one of the southernmost of nine villages near the mouth of the Heart River, which they believed to be the center of the universe.

The village, named On-A-Slant because of its slope toward the river, contained about 75 earthlodges with a village population of around 1000.
The earthlodges were constructed and owned by the women. The frame was made of cottonwood logs, covered with a thick mat of willow, grass and earth. Typical earthlodges were between 20 and 40 feet in diameter and 15 to 20 feet high. In the center of the roof, a circular hole acted as a skylight and smokehole for the firepit.
Unlike most Plains Indian tribes, the Mandan lived in sedentary communities and relied upon a mixture of hunting and agriculture for subsistence. The men hunted while the women tended crops, prepared animal hides and meat, gathered wild berries, wove baskets and made pottery. The Mandan were noted for their skill in processing animal skins and manufacturing pottery, and their villages became trading centers where nomadic tribes came to exchange animal skins for agricultural products.
After prospering on this site for two centuries, a smallpox epidemic hit in 1781 and virtually eliminated the Heart River-region Mandan. The survivors moved north along the Missouri River, eventually joining the Hidatsa near the Knife River.
When Lewis and Clark discovered the deserted On-A-Slant Village in late 1804, it was already in an advanced state of decay, for they reported that the remains included fallen heaps of earth which had covered the houses.
Today, descendants of the Mandan, Hidatsa and Arikara tribes live on the Fort Berthold Reservation surrounding Lake Sakakawea.