In December of 1804, in the area around present-day Washburn, North Dakota, the temperature averaged 4 degrees above zero. The following month, January of 1805, the thermometer plunged further south, reaching 3.4 degrees below zero. But all was snug, or as snug as possible, at Fort Mandan, located on the north bank of the Missouri River, some seven miles below the mouth of the Knife River and directly opposite the lower Mandan Indian village.
The site for this winter haven in the wilderness had been selected during the fall of 1804 by Captain Meriwether Lewis and his co-leader Captain William Clark of the newly formed Corps of Discovery. Work on the fort began on November 3, 1804. Soon after, Private Joseph Whitehouse, a member of the corps, would record in his journal that all of the men were spending their time “diligently in the building of their huts and had made them convertible.”
Clark chose this site for Fort Mandan in an area just south of the Indians’ village and across the river from where most of the Mandans lived. He called the fort site a “hansom plain.” The area was on a low point of ground and was covered with tall and heavy cottonwood trees.
The fort consisted of two rows of huts, set at an angle. There was a palisade on the riverside. There was, of course, a gate and a sentry post. The swivel gun, brought up from their boat, was mounted on the fort. The outside walls of the fort stood eighteen feet high. After a visit by the North West Company trader Francois-Antoine Larocuque, the man mentioned that the fort was built so strong that it was nearly “cannon-ball proof.”
Larocuque’s writing also tell us that Fort Mandan was built in a triangular shape, the two rows of houses making up two sides of the fort. These two rows of houses were not attached to each other, but were connected by a section of fortification that formed a demi-circle. This arrangement allowed the fort to be defended from two sides.
The building of the fort greatly interested the Indians in the area. From the beginning of construction the Mandans made daily crossings of the river just to stand and watch, and also to trade with the soldiers. The fort drew the attention, also, of more than the Mandans and trader Larocuque. On November 4, Clark recorded in his journal the arrival of yet another Frenchman, along with his two Indian wives. It was an event that, unknown to all involved at the time, would create stories that would be repeatedly recorded and told for the next two hundred years and beyond.
Clark’s visitor that fall day was a French Canadian of about forty-five years. The man had at one time worked for the North West Company. But now, he was living with the Hidatsas Indians and working as an independent trader. His name was Toussaint Charbonah. Of his two wives the younger one, who was pregnant, was called Sacagawea. Both women, teenagers actually, were of the Shoshones, a band that had originally lived in the Rocky Mountains near the headwaters of the Missouri River.
The winter the corps spent at Fort Mandan was a long one of guarding against frostbite and avoiding freezing to death. To their amazement, the Mandans seemed to have some kind of mystical ability for enduring the deadly cold and for sustaining life in spite of it. On many occasions the men of the corps were told of one Indian or the other spending the night out on the prairie, with no fire, and only having a single buffalo robe for protection as well as moccasins, antelope leggings, and perhaps a shirt.
And yet, in spite of the Indians capacity for enduring the cold Lewis was kept busy treating the frost bite of some of the Mandans as well as his own men. Once he had to amputate the frozen toes from an Indian boy. But the most common medical problem that Lewis encountered at Fort Mandan was the treating of syphilis. At that point in time, syphilis was considered somewhat commonplace, just as colds and toothaches were. But one medical case Lewis had to deal with, though also common in its self, was not exactly what would be expected to arise within a company made up totally of men. On February 11, 1805, Captain Meriwether Lewis delivered Sacagawea’s baby boy.
The long confining winter could easily have created mental as well as physical problems among the men of the corps. But both Lewis and Clark were wise to this possibility and kept their men occupied. Also relieving the boredom, there were nightly dances held at the Mandan village. The white men were invited and eagerly attended.
At one point during the winter Lewis, probably feeling the length and boredom of the season and looking towards spring, wanted to pull their keelboat up on shore in order to make repairs on it. But, unfortunately, he had waited too long and the boat was tightly frozen into the solid ice of the river. Like his men, he would have to occupy himself otherwise for a while longer.
But at last the first sign of a warmer season came. On the first day of spring it began to rain. Then, by the end of March, great chunks of ice began to float down river. Now their boats could be pulled ashore and repairs made. By the 7th of April the boats were once again back in the water and reloaded.
On April 8, 1805, Captains Meriwether Lewis and William Clark, their men of Corps of Discovery, accompanied by Toussaint Charbonah and his wife Sacagawea with their infant son, left Fort Mandan. They continued their journey westward to discover a continent.
The old site of Fort Mandan has been obliterated by time and the ever-changing course of the river. The site today lies at least partially underwater.