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(ī`dəhō), one of the Rocky Mt. states in the NW United States. It is bordered by Montana and Wyoming (E), Utah and Nevada (S), Oregon and Washington (W), and the Canadian province of British Columbia (N).

Facts and Figures

Area, 83,557 sq mi (216,413 sq km). Pop. (2010) 1,567,582, a 21.1% increase since the 2000 census. Capital and largest city, Boise. Statehood, July 3, 1890 (43d state). Highest pt., Borah Peak, 12,662 ft (3,862 m); lowest pt., Snake River, 710 ft (217 m). Nickname, Gem State. Motto, Esto Perpetua [It Is Perpetual]. State bird, mountain bluebird. State flower, syringa. State tree, white pine. Abbr., ID


Much of Idaho has an unspoiled beauty, with rugged slopes and towering peaks, a vast expanse of timberland, scenic lakes, wild rivers, cascades, and spectacular gorges. From the northern Panhandle, where Idaho is about 45 mi (72 km) wide, the state broadens south of the Bitterroot RangeBitterroot Range,
part of the Rocky Mts., on the Idaho-Mont. line. The main range, running northwest-southeast, includes Trapper Peak (10,175 ft/3,101 m high); Mt. Garfield (10,961 ft/3,341 m), in an east-running spur to the south, is the highest peak.
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 to 310 mi (499 km) in width. The SnakeSnake,
river, 1,038 mi (1,670 km) long, NW United States, the chief tributary of the Columbia; once called the Lewis River. The Snake rises in NW Wyoming, in Yellowstone National Park, flows through Jackson Lake in Grand Teton National Park, then S and W into Idaho and northwest
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 River flows in a great arc across S Idaho; with its tributaries the river has been harnessed to produce hydroelectric power and to reclaim vast areas of dry but fertile land. To the north of the Snake River valley, in central and north central Idaho, are the massive Sawtooth Mts. and the Salmon River Mts., which shelter magnificent wilderness areas, including the Frank Church River of No Return Wilderness, the Selway Bitterroot Wilderness Area, and the Idaho Primitive Area.

In the central and north central regions and in the Panhandle there are tremendous expanses of national forests covering approximately two fifths of the state and constituting one of the largest areas of national forests in the nation. Idaho's jagged granite peaks include Mt. Borah, which is 12,662 ft (3,859 m) high. Hells Canyon, which at one point is 7,900 ft (2408 m) below the mountaintops, is the deepest gorge in North America. The state also contains Craters of the Moon National Monument and Preserve and a protected grove of ancient cedars at Upper Priest Lake.

Rushing rivers such as the Salmon and the Clearwater, and many lakes, notably Lake Pend Oreille, Lake Coeur d'Alene (often described as one of the world's loveliest), and Priest Lake, as well as the state's mountain areas, make Idaho a superb fish and game preserve and vacation land. The state is especially inviting to campers, anglers, and hunters (Idaho has one of the largest elk herds in the nation). The state's climate ranges from hot summers in the arid southern basins to cold, snowy winters in the high wilderness areas of central and northern Idaho. The capital and largest city is BoiseBoise
, city (1990 pop. 125,738), state capital and seat of Ada co., SW Idaho, on the Boise River; inc. 1864. The largest city in Idaho, Boise is an important trade and transportation center.
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; other cities of importance are PocatelloPocatello
, city (1990 pop. 46,080), seat of Bannock co., SE Idaho, between mountains on the Portneuf River near its junction with the Snake (there dammed to form the American Falls Reservoir); inc. 1889.
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 and Idaho FallsIdaho Falls,
city (1990 pop. 43,929), seat of Bonneville co., SE Idaho, traversed by the Snake River; inc. 1900. The chief city of the extensively irrigated upper Snake valley, Idaho Falls is the prosperous commercial and processing center of a cattle, dairy, and farm region
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Manufacturing has recently supplanted agriculture as the most important sector of Idaho's economy. Cattle and dairy goods are among the leading agricultural products. Idaho's chief crops are potatoes (for which the state, easily the nation's largest producer, is famous), hay, wheat, peas, beans, and sugar beets. Electronic and computer equipment, processed foods, lumber, and chemicals are the major manufactured items.

The unspoiled quality of much of Idaho's land has nourished one of the youngest of Idaho's businesses—the tourist trade. Sun ValleySun Valley,
mountain resort city (1990 pop. 938), alt. c.6,000 ft (1,830 m), Blaine co., S central Idaho; inc. 1967. It is a popular year-round resort with both winter and summer sports. It was founded as a ski resort in 1936 by W.
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, one of the nation's best-known year-round vacation spots, is an example of the development of resorts in Idaho. Mining, once the major source of income, and still economically important, produces phosphates, gold, silver, molybdenum, antimony, lead, zinc, and other minerals.

Government, Politics, and Higher Education

Idaho's constitution, adopted in 1889, became effective in 1890 upon statehood. The state's chief executive is a governor elected for a term of four years. The legislature consists of a 42-member senate and an 84-member house of representatives. The state also elects two representatives and two senators to the U.S. Congress and has four electoral votes.

Idaho is a Republican state in national politics but had Democratic governors from 1970 to 1994. Cecil D. Andrus, elected governor in 1970 and reelected in 1974, served as secretary of the interior during the Carter administration; he was elected governor again in 1986 and 1990. Republican Phil Batt, elected governor in 1994, was succeeded by Republican Dirk Kempthorne, elected in 1998 and reelected in 2002. Kempthorne was appointed secretary of the interior in 2006. He was succeeded as governor by Lt. Gov. James E. Risch, also a Republican. Republican Butch Otter was elected to the post later in the year and was reelected in 2010 and 2014. Brad Little, elected in 2018, continued the string of Republicans in the post.

Outstanding among Idaho's institutions of higher learning are the Univ. of Idaho, at Moscow; Idaho State Univ., at Pocatello; and Boise State Univ., at Boise.


Early Explorers and Fur Traders

Probably the first nonnatives to enter the area that is now Idaho were members of the Lewis and Clark expedition in 1805. They were not far ahead of the fur traders who came to the region shortly thereafter. A Canadian, David Thompson of the North West Company, established the first trading post in Idaho in 1809. The next year traders from St. Louis penetrated the mountains, and Andrew Henry of the Missouri Fur Company established a post near present-day Rexburg, the first American trading post established in the area.

In this period the fortunes of the Idaho region were wrapped up with those of the Columbia River region, and the area encompassed by what is now the state of Idaho was part of Oregon country, held jointly by the United States and Great Britain from 1818 to 1846. Fur traders in an expedition sent out by John Jacob Astor came to the Snake River region to trap for furs after having established (1811) a trading post at Astoria on the Columbia River. In 1821 two British trading companies operating in the Idaho region, the North West Company and the Hudson's Bay Company, were joined together as the Hudson's Bay CompanyHudson's Bay Company,
corporation chartered (1670) by Charles II of England for the purpose of trade and settlement in the Hudson Bay region of North America and for exploration toward the discovery of the Northwest Passage to Asia.
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 which, after 1824, came into competition with American mountain menmountain men,
fur trappers and traders in the Rocky Mts. during the 1820s and 30s. Their activities opened that region of the United States to general knowledge. Since the days of French domination there had been expeditions to the upper Missouri River, and in the early 19th
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 also trapping in the area. By the 1840s the two groups had severely depleted the region's fur supply.

Gold, Settlement, and Resistance

In 1846 the United States gained sole claim to Oregon country south of the 49th parallel by the Oregon Treaty with Great Britain. The area was established as a territory in 1848. Idaho still had no permanent settlement when Oregon Territory became a state in 1859 and the eastern part of Idaho was added to Washington Territory. A Mormon outpost founded at Franklin in 1860 is considered the first permanent settlement, but it was not until the discovery of gold that settlers poured into Idaho.

Gold was discovered on the Clearwater River in 1860, on the Salmon in 1861, in the Boise River basin in 1862, and gold and silver were found in the Owyhee River country in 1863. The usual rush of settlers followed, along with the spectacular but ephemeral growth of towns. Most of these settlements are only ghost towns now, but the many settlers who poured in during the gold rush—mainly from Washington, Oregon, and California, with smaller numbers from the east—formed a population large enough to demand new government administration, and Idaho Territory was set up in 1863.

Native Americans, mostly Kootenai, Nez Percé, Western Shoshone, Bannock, Coeur d'Alene, and Pend d'Oreille, became upset by the incursion of settlers and some resisted violently. The federal government had subdued many of these groups by 1858, placing them on reservations. The Bannock were defeated in 1863 and again in 1878. In 1876–77 the Nez Percé, led by Chief Joseph, made their heroic but unsuccessful attempt to flee to Canada while being pursued by U.S. troops.

Development and Disputes

A new mining boom started in 1882 with the discovery of gold in the Coeur d'Alene, and although the gold strike ended in disappointment, it prefaced the discovery there of some of the richest silver mines in the world. Coeur d'Alene and Kellogg became notable mining centers, and the Bunker Hill and Sullivan (a lead mine) became extremely famous mines. Severe labor troubles in the mines at the end of the century led to political uprisings. Frank Steunenberg, who as governor had used federal troops to put down the uprisings, was assassinated in 1905. The trial of William HaywoodHaywood, William Dudley,
1869–1928, American labor leader, known as Big Bill Haywood, b. Salt Lake City, Utah. He began work as a miner at 15 years of age. In 1896 he joined the newly organized Western Federation of Miners, and in 1900 became a member of the executive
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 and others accused of involvement in the murder drew national attention and marked the beginning of the long career of William E. BorahBorah, William Edgar
, 1865–1940, U.S. Senator (1907–40), b. near Fairfield, Ill. Admitted to the bar in Kansas in 1887, after 1890 he became prominent in law and politics at Boise, Idaho.
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 (who had prosecuted the mine leaders) as an outstanding Republican party leader in the state and nation.

The late 19th cent. also witnessed the growth of cattle and sheep ranching, along with the strife that developed between the two groups of ranchers over grazing areas. The coming of the railroads (notably the Northern Pacific) through Idaho in the 1880s and 90s brought new settlers and aided in the founding of such cities as Idaho Falls, Pocatello, and American Falls.

Putting Water and the Atom to Work

Expanding Idaho farming led to private irrigation projects. Some of these aroused public opposition, which led to establishment of state irrigation districts under the Carey Land Act of 1894. The Reclamation Act of 1902 brought direct federal aid. Notable among public reclamation works are the Boise and Minidoka projects. Both public and private, these have also helped to increase the development of Idaho's enormous hydroelectric potential. Further private hydroelectric projects along the Snake River were put into operation between 1959 and 1968.

In 1949 the Atomic Energy Commission built the National Reactor Testing Station in SE Idaho. Now known as the Idaho National Engineering Laboratory, the facility in 1955 provided energy for nearby Arco, the first American town to be lighted by electricity from a nuclear power plant.

Idaho suffered during the recession of the early 1980s but rebounded later in the decade by attracting new business, including high-technology firms. The growth of the winter sports industry has helped make Idaho a leading tourist state. These improvements in its economy made Idaho one of the nation's fastest-growing states in population between 1990 and 2000.


See Federal Writers' Project, Idaho (1938, rev. ed. 1950); M. W. Wells, Idaho: An Illustated History (1980).

The Columbia Electronic Encyclopedia™ Copyright © 2013, Columbia University Press. Licensed from Columbia University Press. All rights reserved.

Idaho State Information

Phone: (208) 334-2411

Area (sq mi):: 83570.08 (land 82747.21; water 822.87) Population per square mile: 17.30
Population 2005: 1,429,096 State rank: 0 Population change: 2000-20005 10.40%; 1990-2000 28.50% Population 2000: 1,293,953 (White 88.00%; Black or African American 0.40%; Hispanic or Latino 7.90%; Asian 0.90%; Other 7.70%). Foreign born: 5.00%. Median age: 33.20
Income 2000: per capita $17,841; median household $37,572; Population below poverty level: 11.80% Personal per capita income (2000-2003): $24,075-$25,902
Unemployment (2004): 4.70% Unemployment change (from 2000): 0.10% Median travel time to work: 20.00 minutes Working outside county of residence: 19.10%

List of Idaho counties:

  • Ada County
  • Adams County
  • Bannock County
  • Bear Lake County
  • Benewah County
  • Bingham County
  • Blaine County
  • Boise County
  • Bonner County
  • Bonneville County
  • Boundary County
  • Butte County
  • Camas County
  • Canyon County
  • Caribou County
  • Cassia County
  • Clark County
  • Clearwater County
  • Custer County
  • Elmore County
  • Franklin County
  • Fremont County
  • Gem County
  • Gooding County
  • Idaho County
  • Jefferson County
  • Jerome County
  • Kootenai County
  • Latah County
  • Lemhi County
  • Lewis County
  • Lincoln County
  • Madison County
  • Minidoka County
  • Nez Perce County
  • Oneida County
  • Owyhee County
  • Payette County
  • Power County
  • Shoshone County
  • Teton County
  • Twin Falls County
  • Valley County
  • Washington County
  • Counties USA: A Directory of United States Counties, 3rd Edition. © 2006 by Omnigraphics, Inc.

    Idaho Parks

    Parks Directory of the United States, 5th Edition. © 2007 by Omnigraphics, Inc.
    The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



    a state in the northwestern USA; one of the mountain states of the far west. Area, 216,400 sq km. Population, 699,000 (1967), of which 47.5 percent (1960) is urban. The capital is Boise. The native inhabitants are Indians (several thousand), forced onto reservations.

    Most of Idaho occupies the southern edges of the Columbia Plateau and the Rocky Mountains that rise up to an elevation of 3,857 m. The southern part is in the Snake River valley. Agriculture is well developed chiefly in the southern part; 35 percent of the cultivated area, approximately 1 million hectares in 1960, is irrigated. Farms account for 29 percent of Idaho’s land area, of which approximately 37 percent is cultivated and the remaining part, as well as most of the state-owned lands, is used for grazing. The main crops are potatoes, sugar beets, wheat, and fodder; Idaho is the nation’s largest sower of potatoes. Horticulture is developed (mostly apples). Stock raising, chiefly of grazing livestock for meat, accounts for about 44 percent of the value of agricultural commodity production. In 1966 there were 1.6 million head of beef cattle and 897,000 sheep. Idaho occupies a prominent position in the USA in the mining of silver, zinc, and lead. Phosphorus is also mined. The manufacturing industry employs 30,000 people. Its branches are the nonfer-rous metallurgy (Kellogg), food, and lumber industries. There is considerable tourism in Sun Valley and other areas.


    The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.


    Forty-third state; admitted on July 3, 1890

    In 1963, Idaho held a centennial celebration marking the anniversary of its becoming a territory of the United States. From June 27 to July 6, numerous activities were sponsored by more than 165 organizations in the Boise area, including “Old Fashioned Bargain Days,” balls, parades, singing, street danc­ing, fireworks, a rifle shoot, sports events, an art exhibit, rodeo, picnics, a poetry reading, an air show, and a historical pageant presenting memorable episodes from the state’s history.

    State capital: Boise
    Nickname: Gem State
    State motto: Esto perpetua (Latin “Let it be perpetual”)
    State bird: Mountain bluebird (Sialia arctcia)
    State fish: Cutthroat trout (Salmo clarki)
    State flower: Syringa (Philadelphus lewisii)
    State folk dance: Square dance
    State fossil: Hagerman horse (Equus simplicidens)
    State fruit: huckleberry (Vaccinium membranaceum)
    State gem: Star garnet
    State horse: Appaloosa
    State insect: Monarch butterfly (Danaus plexippus)
    State raptor: Peregrine falcon (falco peregrinus)
    State song: “Here We Have Idaho”
    State tree: Western white pine (Pinus monticola pinaceae)
    State vegetable: Potato

    More about state symbols at:


    AmerBkDays-2000, p. 498
    AnnivHol-2000, p. 111


    State web site:

    Office of the Governor
    State Capitol Bldg
    2nd Fl
    Boise, ID 83720
    fax: 208-334-3454

    Secretary of State
    700 W Jefferson St
    Rm 203
    Boise, ID 83720
    fax: 208-334-2282

    Idaho Commission for Libraries
    325 W State St
    Boise, ID 83702
    fax: 208-334-4016

    Holidays, Festivals, and Celebrations of the World Dictionary, Fourth Edition. © 2010 by Omnigraphics, Inc.


    a state of the northwestern US: consists chiefly of ranges of the Rocky Mountains, with the Snake River basin in the south; important for agriculture (Idaho potatoes), livestock, and silver-mining. Capital: Boise. Pop.: 1 366 332 (2003 est.). Area: 216 413 sq. km (83 557 sq. miles)
    Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
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