n.
State (pop., 2000: 902,195), northwestern U.S. Bordered by Canada and the U.S. states of North Dakota, South Dakota, Wyoming, and Idaho, it covers 147,046 sq mi (380,849 sq km); its capital is Helena .
Montana straddles the Great Plains to the east and the Rocky Mountains to the west. Unique among the states, its rivers flow into three of the continent's primary watersheds: the Pacific, the Gulf of Mexico, and Hudson Bay. At the time of European settlement the region was inhabited by various Indian tribes, including the Cheyenne , Blackfoot , Nez Percé , and Crow . Most of Montana was obtained by the U.S. through the Louisiana Purchase of 1803. The western part was disputed until 1846, when Britain relinquished its claim to the area. The Lewis and Clark Expedition explored Montana in 180406. St. Mary's Mission, established in 1841 by Roman Catholic missionaries, became the first permanent town as Stevensville. Gold was discovered in the early 1860s; grazing of cattle and sheep was introduced later that decade, leading to bitter battles with the Indians, whose hunting grounds were destroyed. Montana Territory was established in 1864. Though the U.S. troops of George Armstrong Custer were defeated and slain at the Battle of the Little Bighorn in 1876, the Indians ceased fighting in 1877 and were placed on reservations. Montana became the 41st state in 1889. Vast deposits of copper were found in the 1890s, and mining was the economic mainstay for almost a century. The state's economy now emphasizes tourism.