South Dakota, midwestern state in north-central United States; bordered by North Dakota to the north, Minnesota and the Big Sioux River (with Iowa on the other side) to the east, the Missouri River and Nebraska to the south, and Wyoming and Montana to the west.
Land and climate
The geographic center of the United States is in South Dakota, near Castle Rock. South Dakota has 4 main land regions. The Black Hills, a small region on the state's west-central border, is mountainous, with deep canyons and huge rock formations. The Great Plains, covering most of the state's western two-thirds, has rolling, grassy plains and rugged canyons and buttes. The Drift Prairie, in eastern South Dakota, is a low-lying region of rolling hills. The Dissected Till Plains, in the state's southeastern corner, is rolling land cut by glacial streams.
South Dakota's main rivers are the Missouri, which cuts the state roughly in half, and its branches—the Grand, Moreau, Cheyenne, White, James, and Big Sioux. There are no large natural lakes, but artificial ones were created by damming the Missouri. Forests cover less than 4% of the state. South Dakota's climate is dry, with warm summers and cold winters. Principal cities are Sioux Falls and Rapid City.
Wholesale and retail trade lead South Dakota's economy, followed by other service industries, agriculture, manufacturing, and mining. Tourists visit the scenic Black Hills and Mount Rushmore, into which huge heads of Presidents Washington, Jefferson, Lincoln, and Theodore Roosevelt were carved. Beef cattle, hogs, sheep, and wool lead the agricultural share of the economy. Chief crops are corn, wheat, sunflower seeds, rye, flaxseed, and soybeans. Chief manufactured goods are processed foods, machinery, surgical instruments, and electrical equipment. Chief mining products are gold, petroleum, and crushed stone.
South Dakota's constitution was adopted in 1889. The governor serves a 4-year term. The state legislature consists of 35 senators and 70 representatives; all serve 2-year terms. In the U.S. Congress, South Dakota is represented by 2 senators and 1 representative.
Until both gained statehood in 1889, South Dakota shared much of its history with North Dakota. Cheyenne and Arikara peoples lived in the area before the first Europeans, French explorers, arrived about 1743. The area had been claimed for France by explorer Robert La Salle in 1682. France ceded it to Spain in 1762, regained it in 1800, then sold it to the United States under the Louisiana Purchase (1803). The Lewis and Clark expedition explored the area from 1804 to 1806. European-American settlement, at first by fur traders, was dominated by farmers by the 1850s. In 1861 Congress created the Dakota Territory. During the 1860s wars with Native Americans led to the Laramie Treaty (1868), which created the Great Sioux Reservation. In the 1870s a gold rush to the Black Hills violated the treaty, sparking new Native American resistance that ended only with the 1890 massacre of the Sioux at Wounded Knee Creek. Railroads brought rapid settlement to South Dakota, which became the 40th state in 1889. During the Great Depression (1930s), farmers suffered; World War II brought higher farm prices, but mechanized farming put many farmers out of work. Although South Dakota has since broadened its economic base, it was hard hit by the farm crisis of the 1980s.