Fort Mandan

Fort Mandan was the name of the encampment which the Lewis and Clark Expedition built for wintering over in 1804-1805. The encampment was located on the Missouri River approximately twelve miles from the site of present-day Washburn, North Dakota, which developed later. The precise location is not known for certain and is believed now to be under the water of the river. A replica of the fort has been constructed near the original site.

The fort was built of cottonwood lumber cut from the riverbanks. It was triangular in shape, with high walls on all sides, an interior open space between structures, and a gate facing the Missouri River, by which the party would normally travel. Storage rooms provided a safe place to keep supplies. Lewis and Clark shared a room. The men of the Corps of Discovery started the fort on November 2, 1804. They wintered there until April 7, 1805. According to the journals, they built the fort slightly downriver from the five villages of the Mandan and Hidatsa nations.

The winter was very cold, with temperatures sometimes dipping to minus 45 degrees Fahrenheit (-43°C), but the fort provided some protection from the elements. Several of the men of the expedition suffered frostbite due to the severely cold conditions, which affected them even with brief exposure.

In addition to seeking protection during the winter, Captains Meriwether Lewis and William Clark spent much of this period on diplomatic efforts with the several Native American tribes who lived near the fort. As the expedition established the first official contact between the United States and these nations, President Thomas Jefferson had directed the captains to pursue diplomatic goals. They were to try to establish friendly relationships with as many tribes as possible, and to prepare them for the arrival of United States traders to the region. They were also to claim United States territorial sovereignty over the land, which had been occupied by Native Americans for thousands of years. The historic tribes had differing conceptions of property use than did the European Americans.

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