Missouri River - Early Explorers

Early Explorers

In May 1673, the French explorers Louis Jolliet and Jacques Marquette left the settlement of St. Ignace on Lake Huron and traveled down the Wisconsin and Mississippi Rivers, aiming to reach the Pacific Ocean. In late June, Jolliet and Marquette became the first documented European discoverers of the Missouri River, which according to their journals was in full flood. "I never saw anything more terrific," Jolliet wrote, "a tangle of entire trees from the mouth of the Pekistanoui with such impetuosity that one could not attempt to cross it without great danger. The commotion was such that the water was made muddy by it and could not clear itself." They recorded Pekitanoui or Pekistanoui as the local name for the Missouri. However, the party never explored the Missouri beyond its mouth, nor did they linger in the area. In addition, they later learned that the Mississippi drained into the Gulf of Mexico and not the Pacific as they had originally presumed; the expedition turned back about 440 miles (710 km) short of the Gulf at the confluence of the Arkansas River with the Mississippi.

In 1682, France expanded its territorial claims in North America to include land on the western side of the Mississippi River, which included the lower portion of the Missouri. However, the Missouri itself remained formally unexplored until Étienne de Veniard, Sieur de Bourgmont commanded an expedition in 1714 that reached at least as far as the mouth of the Platte River. It is unclear exactly how far Bourgmont traveled beyond there; he described the blond-haired Mandans in his journals, so it is likely he reached as far as their villages in present-day North Dakota. Later that year, Bourgmont published The Route To Be Taken To Ascend The Missouri River, the first known document to use the name "Missouri River"; many of the names he gave to tributaries, mostly for the native tribes that lived along them, are still in use today. The expedition's discoveries eventually found their way to cartographer Guillaume Delisle, who used the information to create a map of the lower Missouri. In 1718, Jean-Baptiste Le Moyne, Sieur de Bienville requested that the French government bestow upon Bourgmont the Cross of St. Louis because of his "outstanding service to France".

Bourgmont had in fact been in trouble with the French colonial authorities since 1706, when he deserted his post as commandant of Fort Detroit after poorly handling an attack by the Ottawa that resulted in thirty-one deaths. However, his reputation was enhanced in 1720 when the Pawnee – who had earlier been befriended by Bourgmont – massacred the Spanish Villasur expedition near present-day Columbus, Nebraska on the Missouri River and temporarily ending Spanish encroachment on French Louisiana.

Bourgmont established Fort Orleans, the first European settlement of any kind on the Missouri River, near present-day Brunswick, Missouri, in 1723. The following year Bourgmont led an expedition to enlist Comanche support against the Spanish, who continued to show interest in taking over the Missouri. In 1725 Bourgmont brought the chiefs of several Missouri River tribes to visit France. There he was raised to the rank of nobility and did not accompany the chiefs back to North America. Fort Orleans was either abandoned or its small contingent massacred by Native Americans in 1726.

The French and Indian War erupted when territorial disputes between France and Great Britain in North America reached a head in 1754. By 1763, France was defeated by the much greater strength of the British army and was forced to cede its Canadian possessions to the English and Louisiana to the Spanish in the Treaty of Paris, amounting to most of its colonial holdings in North America. Initially, the Spanish did not extensively explore the Missouri and let French traders continue their activities under license. However, this ended after news of the British Hudson's Bay Company incursions in the upper Missouri River watershed was brought back following an expedition by Jacques D'Eglise in the early 1790s. In 1795 the Spanish chartered the Company of Discoverers and Explorers of the Missouri, popularly referred to as the "Missouri Company", and offered a reward for the first person to reach the Pacific Ocean via the Missouri. In 1794 and 1795 expeditions led by Jean Baptiste Truteau and Antoine Simon Lecuyer de la Jonchšre did not even make it as far north as the Mandan villages in central North Dakota.

Arguably the most successful of the Missouri Company expeditions was that of James MacKay and John Evans. The two set out along the Missouri, and established Fort Charles about 20 miles (32 km) south of present-day Sioux City as a winter camp in 1795. At the Mandan villages in North Dakota, they expelled several British traders, and while talking to the populace they pinpointed the location of the Yellowstone River, which was called Roche Jaune ("Yellow Rock") by the French. Although MacKay and Evans failed to accomplish their original goal of reaching the Pacific, they did create the first accurate map of the upper Missouri River.

In 1795, the young United States and Spain signed Pinckney's Treaty, which recognized American rights to navigate the Mississippi River and store goods for export in New Orleans. Three years later, Spain revoked the treaty and in 1800 secretly returned Louisiana to Napoleonic France in the Third Treaty of San Ildefonso. This transfer was so secret that the Spanish continued to administer the territory. In 1801, Spain restored rights to use the Mississippi and New Orleans to the United States.

Fearing that the cutoffs could occur again, President Thomas Jefferson proposed to buy the port of New Orleans from France for $10 million. Instead, faced with a debt crisis, Napoleon offered to sell the entirety of Louisiana, including the Missouri River, for $15 million – amounting to less than 3¢ per acre. The deal was signed in 1803, doubling the size of the United States with the acquisition of the Louisiana Territory. In 1803, Jefferson instructed Meriwether Lewis to explore the Missouri and search for a water route to the Pacific Ocean. By then, it had been discovered that the Columbia River system, which drains into the Pacific, had a similar latitude as the headwaters of the Missouri River, and it was widely believed that a connection or short portage existed between the two. However, Spain balked at the takeover, citing that they had never formally returned Louisiana to the French. Spanish authorities warned Lewis not to take the journey and forbade him from seeing the MacKay and Evans map of the Missouri, although Lewis eventually managed to gain access to it.

Meriwether Lewis and William Clark began their famed expedition in 1804 with a party of thirty-three people in three boats. Although they became the first Europeans to travel the entire length of the Missouri and reach the Pacific Ocean via the Columbia, they found no trace of the Northwest Passage. The maps made by Lewis and Clark, especially those of the Pacific Northwest region, provided a foundation for future explorers and emigrants. They also negotiated relations with multiple Native American tribes and wrote extensive reports on the climate, ecology and geology of the region. Many present-day names of geographic features in the upper Missouri basin originated from their expedition.