Étienne de Veniard, Sieur de Bourgmont was a French explorer who documented his travels on the Missouri and Platte rivers in North America and made the first European maps of these areas in the early 18th century. He wrote two accounts of his travels, which included descriptions of the Native American tribes he encountered. In 1723, he established Fort Orleans, the first European fort on the Missouri River, near the mouth of the Grand River, and present-day Brunswick, Missouri. In 1724, he led an expedition to the Great Plains of Kansas to establish trading relations with the Padouca.

The Missouri River is a river in the Central and Mountain West regions of the United States. The nation's longest, it rises in the eastern Centennial Mountains of the Bitterroot Range of the Rocky Mountains of southwestern Montana, then flows east and south for 2,341 miles (3,767 km) before entering the Mississippi River north of St. Louis, Missouri. The river drains semi-arid watershed of more than 500,000 square miles (1,300,000 km2), which includes parts of ten U.S. states and two Canadian provinces. Although a tributary of the Mississippi, the Missouri River is slightly longer and carries a comparable volume of water. When combined with the lower Mississippi River, it forms the world's fourth-longest river system.