The Mighty Missouri River
The Mighty Missouri River, a significant tributary of the Mississippi, carves its path across the heartland of the United States, etching a legacy that intertwines with the nation’s history, exploration, and westward expansion. Stretching an impressive 2,540 miles, it reigns as the longest river in the country, a vital artery that has shaped landscapes and influenced human endeavors for centuries.
The Missouri River’s journey begins high in the Rocky Mountains of Montana, near the town of Three Forks. Here, at an elevation of 4,045 feet, the confluence of the Jefferson and Madison Rivers marks its official genesis. Shortly downstream, the Gallatin River joins the nascent Missouri, adding its waters to the growing current. From this mountainous cradle, the Mighty Missouri River embarks on a southeasterly course, traversing the vast expanse of the Missouri River Basin. It flows through North Dakota, South Dakota, and Nebraska, each state leaving its unique imprint on the river’s character. Finally, the Mighty Missouri River reaches Missouri, where it merges with the Mississippi River just north of the bustling city of St. Louis, completing its epic voyage.
The early 19th century witnessed a pivotal moment in American history – the Louisiana Purchase. In 1803, the United States, initially seeking to acquire the port of New Orleans from France, unexpectedly gained control of a vast territory encompassing all the lands between the Mississippi River and the headwaters of the Mighty Missouri River. This acquisition, totaling approximately 828,800 square miles, ignited a fervent interest in westward expansion and exploration.
Fueled by this newfound opportunity, President Thomas Jefferson, a staunch advocate for western development, secured a $2,500 appropriation from Congress to fund a U.S. Army expedition to explore the newly acquired lands, extending all the way to the Pacific Ocean. This expedition, later immortalized as the Corps of Discovery, was tasked with meticulously documenting the Native American tribes encountered, the diverse geography, the prevailing climate, and the flora and fauna of the region. Furthermore, they were to assess the potential influence of British and French-Canadian hunters and trappers who had already established a presence in the area. A primary objective for Jefferson was the discovery of a navigable waterway that would connect the eastern United States to the western coast, facilitating trade and communication across the continent.
Jefferson entrusted the leadership of this crucial expedition to Meriwether Lewis, a 28-year-old Army Captain. Lewis, in turn, selected his former Army comrade, William Clark, a 32-year-old Second Lieutenant, to share the responsibilities of leading the Corps of Discovery. Despite Clark’s lower official rank, Lewis concealed this from the men and consistently referred to Clark as "Captain," ensuring a sense of shared leadership and mutual respect throughout the expedition.
On May 14, 1804, Lewis and Clark embarked on their historic journey from St. Louis, Missouri, accompanied by a dedicated team of 45 men, a sturdy 55-foot keelboat, and two large canoes. Their mission was to trace the Mighty Missouri River to its source, charting its course and documenting its features for the first time. After several months of arduous travel, they reached the headwaters of the Missouri River, the point where the Jefferson, Madison, and Gallatin Rivers converge. In his journal entry dated July 28, 1805, Meriwether Lewis recorded their decision to name the three rivers after prominent figures: "Both Capt. C. and myself corresponded in opinion with respect to the impropriety of calling either of these [three] streams the Missouri and accordingly agreed to name them after the President of the United States and the Secretaries of the Treasury and state."
Following the Jefferson River to the Beaverhead River and eventually reaching the Continental Divide, Lewis and Clark believed they were approaching the definitive headwaters of the Mighty Missouri River. However, upon ascending the final ridge towards the Continental Divide, Meriwether Lewis was met with a surprising sight: instead of the expected plains and a river flowing towards the Pacific, he encountered yet more mountains, underscoring the vastness and complexity of the western landscape.
While Lewis and Clark’s expedition remains the most famous exploration of the Missouri River, it is important to acknowledge the presence of early trappers and traders who preceded them. The first Europeans to set eyes on the river were the French explorers Louis Jolliet and Father Jacques Marquette. Interestingly, a common misconception surrounds the naming of the river and the state of Missouri. Father Jacques Marquette, in May 1673, referred to the river as "Pekitanoui," meaning "muddy." However, the river and the state were actually named after the Siouan Indian tribe, whose Illinois name, Ouemessourita, translates to "those who have dugout canoes." Throughout history, the river has been known by a multitude of names, reflecting the diverse cultures and perspectives of those who interacted with it: Big River, Big Muddy, Emasulia sipiwi, Eomitai, Katapan Mene Shoska, Le Riviere des Missouri, Mini Sose, Missoury River, Ni-sho-dse, Nudarcha, Rio Misuri, Riviere de Pekitanoni, Riviere de Saint Philippe, Le Missouri, Le Riviere des Osages, Missures Flu, Miz-zou-rye River, Niutaci, Pekitanoui, River of the West, and Yellow River.
For several decades following its initial discovery, the Mighty Missouri River remained largely unexplored and uncharted. It was not until Étienne de Veniard and Sieur de Bourgmont embarked on upstream voyages in 1713 and 1714 that detailed descriptions began to emerge. Bourgmont is credited with being the first to use the name "Missouri" to refer to the river. In 1723, Bourgmont and Etienne de Veniard established Fort Orleans, the first fort on the Missouri River, located near the mouth of the Grand River near Brunswick, Missouri. The fort was named in honor of the Duke of Orléans.
The extent of Bourgmont’s travels up the Missouri River remains unclear, but he is also recognized as the first European to discover the Platte River. The Treaty of Paris in 1763, which concluded the French and Indian War, transferred control of the Missouri River to the Spanish. However, the Spanish did not undertake extensive explorations of the river, allowing French fur traders to continue their activities along its waterways.
Before the Lewis and Clark expedition, the most significant exploration was the MacKay and Evans Expedition of 1795-1797. James MacKay and John Evans were commissioned by the Spanish to locate a route to the Pacific Ocean and to order the British to vacate the upper Missouri River region. McKay and Evans produced a comprehensive map of the upper Missouri River, which would later prove invaluable to Lewis and Clark.
In later years, the Mighty Missouri River became the primary starting point for numerous trails that opened up the American West, including the California, Mormon, Oregon, and Santa Fe Trails. St. Joseph, Missouri, served as the eastern terminus of the Pony Express. The construction of the Hannibal Bridge in Kansas City in 1869 marked the first bridge to span the Missouri River. Soon after, paddle steamers began navigating the river, playing a crucial role in facilitating settlement in the Dakotas and Montana. Fort Benton, Montana, represented the northernmost navigable point on the Missouri before extensive navigation improvements were implemented.
Over the subsequent century, extensive construction of dams, dikes, and levees took place along the river for flood control purposes. Today, approximately 35% of the river is impounded. Notably, the Missouri National Recreational River, a 100-mile National Park situated between Gavins Point Dam and Ponca State Park, Nebraska, along the Nebraska-South Dakota border, preserves one of the last significant stretches of the free-flowing river. This park showcases the islands, bars, chutes, and snags that once characterized the "Mighty Mo." It also protects the historic ruins of Fort Randall, Spirit Mound, an important cultural site for Native Americans, and the Meridian Bridge, an engineering marvel from the 1920s.