At that time, there was still rivalry with British traders on the upper Missouri.

He interrupted his studies to trap and trade on the upper Missouri and Columbia Rivers from 1837 to 1839.

When they left St. Louis, the big land of the upper Missouri and beyond was mostly a rumor.

Later, in the summer and fall the water levels dropped, and there was "low water" on the upper Missouri.

He learned of the Mandan country on the upper Missouri.

Their first year of service was guarding rail lines in upper Missouri.

Earth lodge tales from the upper Missouri.

Fort Union was the most important fur trading post on the upper Missouri until 1867.

To the southwest is the Mandan country on the upper Missouri.

From the first year they traded in buffalo robes with the Mandan villages on the upper Missouri.