Oklahoma, located near the central part of the conterminous United States, has an area of 181,185 sq km (69,956 sq mi) and ranks 18th in size among the states. It is bordered by Kansas and Colorado on the north, by New Mexico on the west, by Texas on the west and south, and by Missouri and Arkansas on the east. It ranks 28th in population. Formed by the union of Oklahoma Territory and Indian Territory, Oklahoma was admitted as the 46th state on Nov. 16, 1907. Oklahoma is a Choctaw word meaning "red man." Oklahoma has been nicknamed the "Sooner State" for the settlers who tried to enter the area and claim land sooner than it was legal to do so. The state is an important producer of agricultural products, especially wheat, cattle, and cotton, and mineral fuels, notably petroleum products and coal. LAND AND RESOURCES Oklahoma is located in the transitional zone between the eastern and western parts of the nation. The Ozark Plateau and the Ouachita Mountains are similar to the Appalachian highlands to the east; the central part of the state constitutes the southern part of the Central Lowlands; and northwestern Oklahoma is a part of the \TGreat Plains\t. Elevation increases from 88 m (289 ft) near the southeastern corner of the state to 1,516 m (4,973 ft) on Black Mesa in the northwestern corner of the Panhandle. The Ouachita Mountains are a series of long, steep-sloped, parallel ridges formed largely by folding and faulting, many capped by a massive layer of sandstone. The region has the greatest relief in Oklahoma. The \TOzark Mountains\t, or Ozark Plateau, and the Ouachitas are separated by the Arkansas River. The Ozarks are composed of horizontal layers of rocks, mainly limestones and shales. The Wichita Mountains in the southwest are largely granite, rhyolite, and gabbro peaks with boulder-strewn slopes, and much of the Arbuckle region in the south central part of the state is formed of ribbed edges of limestone with complex folds and faults. The Osage Plains in central Oklahoma are underlain by nearly horizontal rocks that dip slightly westward; they are divided into the Eastern Lowlands, Osage Prairies, Cross Timbers, and Western Red Prairies. The Great Plains have elevations that increase westward from 610 to almost 1,525 m (2,000 to 5,000 ft). The northern limits of the Gulf Coastal Plain in the southeast constitute an area of soft sandstone, shale, and limestone. Soils Oklahoma's soils correspond to its physiographic and climatic regions. About two-thirds of the soils developed under grass and the remainder under forest. The prairie soils in the west are extremely fertile when moisture is sufficient. Rivers and Lakes All drainage from Oklahoma occurs either by the \TArkansas River\t, which crosses the northeastern quarter of the state, or the \TRed River\t, which follows the southern boundary. The \TCanadian River\t, the Cimarron, the Neosho, and the Illinois are major tributaries of the Arkansas. The North Fork of the Red River and the Washita, the Kiamichi, and the Little rivers flow into the Red River. Several large artificial lakes have been formed by the damming of rivers. Eufaula Reservoir, covering 427 sq km (165 sq mi) at normal level, is the largest. Climate Oklahoma climate varies from the high, arid continental type in the west to the low, humid subtropical type in the southeast. Rainfall increases from less than 381 mm (15 in) annually in the western Panhandle to more than 1,270 mm (50 in) in the Ouachita Mountains. In the higher, more arid, western part of the state, yearly temperatures range from -23 deg C (-10 deg F) in January to above 38 deg C (100 deg F) in July. In the southeast, temperatures vary from about 0 deg C (32 deg F) in winter to 32 deg C (90 deg F) in July. Vegetation and Animal Life Grasses are the dominant vegetation in the plains areas of Oklahoma. Shortgrasses and bunchgrasses are common in the northwest, and savanna and tall grasses occupy large areas of central and southwestern Oklahoma. The Cross Timbers areas in the central part of the state are covered with blackjack oak and post oak trees. Oak-hickory and oak-pine forests are located in the Ozark and Ouachita regions, respectively. Deer, coyotes, rabbits, and numerous smaller animals are common. The Wichita Mountain wildlife refuge has small herds of buffalo, long-horned cattle, moose, deer, and prairie dogs. Natural Resources Oklahoma has long been recognized for the variety of minerals mined. Petroleum was first obtained from a well in 1859, and since 1896, Oklahoma has been a leading petroleum-producing state. Large coal reserves are located in eastern Oklahoma. Glass sand, salt, gypsum, lead, copper, limestone, dolomite, and granite are also found in great quantities. Much of Oklahoma's abundant hydroelectric power potential has been harnessed since World War II. The fertile plains are covered with wheat farms and cattle ranches. Oklahoma's forests support a paper industry. PEOPLE The population of Oklahoma (1990 resident census) is 3,145,585. In 1990 the state's population was 82.1% white, 7.4% black, 8% Indian, 1.1% Asian, and 2.7% Hispanic. Population growth in the period 1970-80 totaled 18.2%, most from in-migration. Between 1980 and 1990 the growth rate slowed to 4%. About 70% of the people are under 45 years of age. \TOklahoma City\t and \TTulsa\t are the two largest cities. \TLawton\t, Norman, and Midwest City each have populations greater than 50,000. The Southern Baptist and Methodist religious denominations have the largest memberships in the state. Education The first schools were established by mission groups and the governments of the Five Civilized Tribes soon after the tribes' arrival in the 1830s. When Oklahoma was settled by whites, sections in each township were set aside for schools. A state-supported system of universities now operates in Oklahoma (see \TOklahoma, state universities of\t). Four junior colleges and ten universities are privately supported. Oklahoma has a statewide system of public libraries. Cultural and Historic Sites Among Oklahoma's museums are the National Cowboy Hall of Fame and Western Heritage Center in Oklahoma City, the Gilcrease Institute of American History and Art and the Philbrook Art Center in Tulsa, and the Woolaroc Museum near Bartlesville. The Will Rogers Memorial is in Claremore. Indian City U.S.A. at Anadarko displays authentic Indian dwellings of various Plains tribes. The Oklahoma Historical Society, supported by the state, directs activities at the many regional museums. Noted historic sites include restored Fort Gibson, the Cherokee Village complex at Tahlequah, Spiro Mound near Spiro, and the Washita battlefield near Cheyenne. Oklahoma City and Tulsa each have symphony orchestras and theater groups. Ardmore, Clinton, Enid, Muskogee, and other cities have privately supported theater centers. Oklahoma's numerous parks and wildlife refuges include the Ouachita National Forest and the Chickasaw National Recreation Area. College-level football is very popular in the state. Communications Commercial radio broadcasting began in Oklahoma in 1921, and television broadcasting in 1949. The state has numerous daily and weekly newspapers. ECONOMIC ACTIVITY Since 1950 the economy of Oklahoma has changed dramatically. Oklahoma is no longer basically an agricultural state--mining (primarily oil), manufacturing, and the various service industries contribute much more to the gross state product than does agriculture. The worldwide decline in oil prices in the mid-1980s, however, combined with depressed farm prices, affected the state's economy very adversely into the late 1980s. Agriculture Agriculture in Oklahoma has changed from that of small farms growing a variety of crops to large farms and ranches specializing in specific crops or animal production. The production of beef cattle contributes most to agricultural revenues. winter wheat is the most important crop; other significant crops are hay, corn, sorghum grain, soybeans, and peanuts. The economic crisis that afflicted U. S. agriculture in the 1980s was particularly hard and prolonged in Oklahoma. State data show that the number of farms fell from 73,000 to 70,000 in 1985-87, and subsequently thousands of farmers still faced foreclosure. Manufacturing Because Oklahoma is a part of the "Sun Belt" and has a favorable tax structure, an adequate supply of energy, and a capable work force, several large industries have relocated in the state. Manufacturing is highly diversified. Leading industries in Oklahoma include the manufacture of petroleum and coal products, nonelectrical machinery, food products, fabricated metal products, and rubber and plastics products. The chief manufacturing area lies in a belt from Oklahoma City northeast to the Kansas-Missouri-Oklahoma border. Mining Petroleum, natural gas, and natural-gas liquids (such as natural gasoline and butane) dominate the mining and energy sectors in Oklahoma. The state is a national leader in fossil-fuel production, including coal as well as petroleum and related fuels. Much of the natural gas goes by pipeline elsewhere in the country, for use as cooking and heating fuel. Many major petroleum firms have offices in Oklahoma, particularly in Tulsa, Bartlesville, and Oklahoma City. The value of nonfuel mineral production in Oklahoma is far less than that derived from fossil fuels, but it is nonetheless significant. Such minerals include iodine, gypsum, limestone, and clays. Energy Oklahoma uses its abundant supplies of gas, oil, and coal to produce nearly all of its electric power. A small proportion of electricity is produced by hydroelectric plants, located mostly in northeastern Oklahoma. Forestry The Ouachita Mountains are densely forested with pine, oak, and hickory, and some cypress grows in the valleys of the Little and the Mountain Fork rivers. Pine-tree farming, now the dominant regulated land use in the mountains, supplies a large paper mill in Valliant. Sawmills are common throughout both the Ouachita and Ozark regions. Transportation and Tourism Railroads, first built in Oklahoma in the 1870s, were an important factor in the state's development. Extensive road and highway networks, however, have increasingly supplanted railroads for freight transport as well as passenger travel. The McClellan-Kerr Arkansas River Navigation System (1971) links the Tulsa area with the Mississippi River and thus the Gulf of Mexico. Tourism is a growing economic activity in Oklahoma. GOVERNMENT Oklahoma state government operates under its original constitution as approved by the voters in 1907. The constitution has, however, been amended several times. The state legislature meets annually. The governor and state officers are elected for 4-year terms, as are state senators. State representatives serve 2 years. Supreme court judges, after being elected, serve for life or until retirement. Although a large majority of Oklahomans are registered as Democrats, it is not unusual for a Republican to be elected governor or U.S. senator. Oklahoma has 77 counties, each electing its own officers. The chief officials in each county are the 3 county commissioners. The state has 100 incorporated cities with populations of 2,500 or more as well as about 560 incorporated towns and villages. The larger cities are usually governed by a mayor and city council that, in turn, appoint a city manager and approve those selected to serve on various boards and committees. In 1969 the Oklahoma legislature authorized the division of the state into 11 sub-state planning districts to coordinate law enforcement, health and manpower planning, and community and economic development. They also serve to coordinate work of the local community with state and federal agencies. HISTORY Indians lived in and migrated back and forth across what is now Oklahoma as they hunted for animals and food. The earliest people lived some 15,000 years ago in caves and under rock shelters in the western part of the state. The Spanish were the first Europeans to explore Oklahoma. Francisco Vazquez de \TCoronado\t crossed the western part of the state in 1541. Later Spanish explorers also crossed western and southern Oklahoma but formed no settlements in the area. The French explored the streams in eastern Oklahoma, and the trader Auguste Pierre Chouteau (see \TChouteau\t family) established the first permanent settlement--now Salina--in 1817. In 1803 the United States purchased the Louisiana Territory from France, but the limits of the purchased area were not known until the Adams-Onis Treaty was completed in 1819. The Red River and the 100 deg west meridian became boundaries of the American territory and today form the southern and most of the western boundary of Oklahoma. The Panhandle, extending westward to 103 deg west longitude, belonged to Spain until 1821, to Mexico from 1821 to 1836, and to the nation of Texas until 1850, when it became U.S. territory. The Panhandle remained unorganized territory until attached to Oklahoma Territory in 1890. After the \TLouisiana Purchase\t the area was explored by traders. The traders shipped the goods they bought from Indians downriver past St. Louis to New Orleans on flatboats. In 1808 the powerful \TOsage\t tribe ceded to the United States all of eastern Oklahoma north of the Arkansas River, and in 1818 the \TQuapaw\t Indians ceded all claims to lands south of the Arkansas in present-day Oklahoma and Arkansas. This cleared the way for enactment of President Jackson's policy of Indian "consolidation." The government of the United States negotiated treaties with the Indians living in the Southeastern part of the nation whereby they would relinquish their Eastern lands in exchange for territory encompassing nearly all of present-day Oklahoma. The \TFive Civilized Tribes\t--\TCherokee\t, \TChickasaw\t, \TChoctaw\t, \TCreek\t, and \TSeminole\t--were primarily successful farmers or professionals who adopted many cultural traits of the white settlers. Their removal (1830-40) over the various "trails of tears" resulted in many deaths and severe hardship. The Choctaws and Cherokees were the first moved. The Choctaws were settled south of the Arkansas and Canadian rivers, the Cherokees on land north and east of the Arkansas River. The Creeks were settled north of the Canadian and west of the Arkansas. At first the Chickasaws were located in the Choctaw Nation and the Seminoles in the Creek Nation, but later each tribe was allotted its own area. To clear the way for the settlement of the Eastern Indians on Oklahoma lands, the United States government entered into a series of complicated negotiations with the indigenous groups, culminating in a treaty signed Aug. 24, 1835. Under this treaty the \TComanche\t, \TWichita\t, and associated tribes agreed not to make war on persons traveling through their territory and not to interfere with those Eastern Indians who wished to hunt in the territory. The \TKiowa\t signed a similar document two years later. In the new \TIndian Territory\t the Five Civilized Tribes organized representative governments, established towns, and developed farms and businesses until the Civil War disrupted their way of life. As many of the Indians were slaveholders, the people of the Five Civilized Tribes were divided in loyalty between the Union and the Confederacy. During the Civil War many homes and towns were destroyed, some battles and several skirmishes were fought, and many Indians were forced to leave their respective nations. Following the Civil War the U.S. government declared these Indians to have been allies of the Confederacy and forced the Five Civilized Tribes to give up their western lands for considerations of 15 to 30 cents an acre. Much of the western area was then divided into reservations on which various Plains Indians--ARAPAHO, \TCheyenne\t, \TPawnee\t, Kiowas, Comanches, Wichitas, and smaller tribes--were settled. The Unassigned Lands near the center of Oklahoma, Old Greer County in the southwest, and the Panhandle were not allotted to any tribes. Texas veterans of the Civil War settled in Old Greer County, and cattle raisers staked out ranches in the Panhandle. Many people, especially the "Boomers" under the leadership of Capt. David L. Payne, demanded that the Unassigned Lands be opened to settlement. On Apr. 22, 1889, the "horse race," or "run," method was used to claim the plots in the Unassigned Lands. At later dates the Cheyenne-Arapaho reservation, the Cherokee Outlet, and several other reservations were also established by this method. Enid, Guthrie, and Oklahoma City grew into cities of 5,000 people or more within six hours. The Kiowa-Comanche lands were opened by lottery. The Unassigned Lands was officially designated Oklahoma Territory on May 2, 1890. With the establishment of the Oklahoma Territory and the rapid increase in population came pressure for statehood. At the same time, settlers demanded that the Indians be confined to certain areas and that the remainder be opened to homesteading. Eventually the U.S. Congress appointed a commission, headed by Sen. Henry L. Dawes, which entered ten years of negotiations with the Five Civilized Tribes. The Dawes Commission was successful in persuading the tribes to divide their lands among the individual members and to abolish their tribal governments. Allotment of the Indian lands began on Apr. 1, 1899, and was not completed until 1910. By that time the two halves of Oklahoma had been joined in statehood on Nov. 16, 1907. Before this date Indian protest culminated in a meeting in Muskogee on July 14, 1905, when representatives of all sections of the Indian Territory adopted a constitution for a state to be called Sequoyah. Congress, however, refused to recognize the state. Since statehood in 1907 many changes have taken place. Oklahoma has changed from a rural to an urban state, from an agricultural economy to one based on industry. Its population has increased with each census except 1930 and 1940, during the difficult times of the \TDust Bowl\t and the Depression of the 1930s. Oklahoma has also become an important center for military activities. Petroleum production remains important, but since 1982 the industry has experienced a downturn that has contributed to Oklahoma's sluggish economy of the 1980s and early 1990s. John W. Morris Bibliography: Federal Writers' Project, Oklahoma: A Guide to the Sooner State, rev. ed. (1957); Gibson, Arrell, The Oklahoma Story (1978) and The History of Oklahoma (1984); Jordan, H. Glenn, ed., Indian Leaders (1979); Kirkpatrick, S. A., et al., The Oklahoma Voter: Politics, Elections and Political Parties in the Sooner State (1977); Lage, Gerald M., et al., A Profile of Oklahoma: Economic Development (1977); McReynolds, Edwin C., et al., Oklahoma: The Story of Its Past and Present (1961; repr. 1985); Marriott, Alice, and Rachlin, C. K., Oklahoma (1973); Morgan, Howard W. and Anne H., Oklahoma: A Bicentennial History (1977); Morris, John W., ed., Cities of Oklahoma (1979) and Geography of Oklahoma (1977); Morris, John W., et al., Historical Atlas of Oklahoma (1986); Scales, J. R., and Goble, D., Oklahoma Politics: A History (1982); Skaggs, Jimmy, ed., The Range and Ranch in Oklahoma (1978); Stout, Joseph A., ed., Frontier Adventurers (1976); Thiel, Sidney, The Oklahoma Land Rush (1973); Thompson, J., Closing the Frontier (1986); Wright, M.H., A Guide to the Indian Tribes of Oklahoma (1987).