Idaho prior to European settlement was inhabited by Native American peoples, some of whom still live in the area. In the early 19th century, Idaho was considered part of the Oregon Country, an area disputed between the U.S. and the United Kingdom. It officially became U.S. territory with the signing of the Oregon Treaty of 1846, but a separate Idaho Territory was not organized until 1863, instead being included for periods in Oregon Territory and Washington Territory. Idaho was eventually admitted to the Union on July 3, 1890, becoming the 43rd state.
Forming part of the Pacific Northwest (and the associated Cascadia bioregion), Idaho is divided into several distinct geographic and climatic regions. In the state's north, the relatively isolated Idaho Panhandle is closely linked with Eastern Washington, with which it shares the Pacific Time Zone – the rest of the state uses the Mountain Time Zone. The state's south includes the Snake River Plain (which has most of the population and agricultural land), while the south-east incorporates part of the Great Basin. Idaho is quite mountainous, and contains several stretches of the Rocky Mountains. The United States Forest Service holds about 38% of Idaho's land, the most of any state.
Industries significant for the state economy include manufacturing, agriculture, mining, forestry, and tourism. A number of science and technology firms are either headquartered in Idaho or have factories there, and the state also contains the Idaho National Laboratory, which is the country's largest Department of Energy facility. Idaho's agricultural sector supplies many products, but the state is best known for its potato crop, which comprises around one-third of the nationwide yield. The official state nickname is the "Gem State", which references Idaho's reputation for gemstones and, more broadly, its many wilderness areas.
The name's origin remains a mystery. In the early 1860s, when the United States Congress was considering organizing a new territory in the Rocky Mountains, eccentric lobbyist George M. Willing suggested the name "Idaho", which he claimed was derived from a Shoshone language term meaning "the sun comes from the mountains" or "gem of the mountains". Willing later claimed he had invented the name. Congress decided to name the area Colorado Territory when it was created in February 1861. Thinking they would get a jump on the name, locals named a community in Colorado "Idaho Springs".
However, the name "Idaho" did not fall into obscurity. The same year Congress created Colorado Territory, a county called Idaho County was created in eastern Washington Territory. The county was named after a steamship named Idaho, which was launched on the Columbia River in 1860. It is unclear whether the steamship was named before or after Willing's claim was revealed. Regardless, part of Washington Territory, including Idaho County, was used to create Idaho Territory in 1863.