In the 1850s, settlers began moving into the Beaverhead and Big Hole valleys from the Oregon Trail and into the Clark's Fork valley. In 1847, Fort Benton was built as the uppermost fur-trading post on the Missouri River.

Mary's, established in 1841 near present-day Stevensville. The first permanent settlement by Euro-Americans in what today is Montana was St. governments and was known as the Oregon Country. Until the Oregon Treaty of 1846, land west of the continental divide was disputed between the British and U.S. The trading post Fort Raymond (1807–1811) was constructed in Crow Indian country in 1807. Indigenous peoples in the region were also decimated by diseases introduced by fur traders to which they had no immunity. Though the increased interaction between fur traders and indigenous peoples frequently proved to be a profitable partnership, conflicts broke out when indigenous interests were threatened, such as the conflict between American trappers and the Blackfeet. Subsequent to and particularly in the decades following the Lewis and Clark Expedition, European, Canadian and American traders operated a fur trade, trading with indigenous peoples, in both eastern and western portions of what would become Montana. Īs part of the Missouri River watershed, all of the land in Montana east of the Continental Divide was part of the Louisiana Purchase in 1803. A part of southeastern Montana was used as a corridor between the Crows and the related Hidatsas in North Dakota. The smaller Pend d'Oreille and Kalispel tribes lived near Flathead Lake and the western mountains, respectively. Historic tribes encountered by Europeans and settlers from the United States included the Crow in the south-central area, the Cheyenne in the southeast, the Blackfeet, Assiniboine, and Gros Ventres in the central and north-central area, and the Kootenai and Salish in the west. Various indigenous peoples have inhabited the territory of the present-day state of Montana for thousands of years. Other names, such as Shoshone, were suggested, but the Committee on Territories decided that they had discretion to choose the name, so the original name of Montana was adopted. Cox complained that the name was a misnomer given that most of the territory was not mountainous and thought a Native American name would be more appropriate than a Spanish one. Samuel Cox, also of Ohio, objected to the name. When Ashley presented a bill to establish a temporary government in 1864 for a new territory to be carved out of Idaho, he again chose Montana Territory. Harding (Oregon), who complained that Montana had 'no meaning'. The name was changed by representatives Henry Wilson (Massachusetts) and Benjamin F. The name Montana was added in 1863 to a bill by the United States House Committee on Territories (chaired at the time by James Ashley of Ohio) for the territory that would become Idaho Territory. The name Montana comes from the Spanish word montaña, which in turn comes from the Latin word montanea, meaning 'mountain' or more broadly 'mountainous country.' Montaña del Norte was the name given by early Spanish explorers to the entire mountainous region of the west. Montana's fastest-growing sector is tourism, with 12.6 million tourists (as of 2019) visiting the state each year.

The health care, service, and government sectors are also significant to the state's economy. Other significant economic resources include oil, gas, coal, mining, and lumber. Its economy is primarily based on agriculture, including ranching and cereal grain farming. Montana has no official nickname but several unofficial ones, most notably 'Big Sky Country', 'The Treasure State', 'Land of the Shining Mountains', and ' The Last Best Place'. The state has a reputation for a libertarian bent in popular opinion and policy. The western half of Montana contains numerous mountain ranges, while the eastern half is characterized by western prairie terrain and badlands, with smaller mountain ranges found throughout the state. Its state capital is Helena, while the largest city is Billings. It is the fourth-largest state by area, the eighth-least populous state, and the third-least densely populated state. It is bordered by Idaho to the west, North Dakota and South Dakota to the east, Wyoming to the south, and the Canadian provinces of Alberta, British Columbia, and Saskatchewan to the north. Montana ( / m ɒ n ˈ t æ n ə/ ( listen)) is a state in the Mountain West division of the Western United States.

Montana precipitation totals