Arkansas () is a state in the south central region of the United States, home to more than three million people as of 2018. Its name is from the Osage language, of Siouan derivation; it denoted their related kin, the Quapaw people. The state's diverse geography ranges from the mountainous regions of the Ozark and the Ouachita Mountains, which make up the U.S. Interior Highlands, to the densely forested land in the south known as the Arkansas Timberlands, to the eastern lowlands along the Mississippi River and the Arkansas Delta.
Arkansas is the 29th largest by area and the 33rd most populous of the 50 United States. The capital and most populous city is Little Rock, located in the central portion of the state, a hub for transportation, business, culture, and government. The northwestern corner of the state, such as the Fayetteville–Springdale–Rogers Metropolitan Area and Fort Smith metropolitan area, is a population, education, and economic center. The largest city in the state's eastern part is Jonesboro. The largest city in the state's southeastern part is Pine Bluff.
The Territory of Arkansas was admitted to the Union as the 25th state on June 15, 1836. Much of the Delta had been developed for cotton plantations, and the state landowners there largely depended on enslaved African Americans as workers. In 1861, Arkansas seceded from the United States and joined the Confederate States of America during the Civil War.
On returning to the Union in 1868, the state continued to suffer due to its reliance on the large-scale plantation economy. Cotton continued as the leading commodity crop, although the cotton market declined. Because farmers and businessmen did not diversify and there was little industrial investment, the state fell behind in terms of its economy and opportunities for residents.
White rural interests dominated the state's politics by disenfranchisement of African Americans and by refusal to reapportion the legislature. It was not until after the civil rights movement and federal intervention that more African Americans were able to vote. The Supreme Court overturned rural domination in the South and other states that had refused to reapportion their state legislatures, or retained rules based on geographic districts. In the landmark ruling of one man, one vote, it ruled that states had to organize both houses of their legislatures by districts that held approximately equal populations, and that these had to be redefined as necessary after each decade's census.
Following World War II, Arkansas began to diversify its economy. In the 21st century, its economy is based on service industries, aircraft, poultry, steel, and tourism; along with important commodity crops of cotton, soybeans and rice.
The culture of Arkansas is observable in museums, theaters, novels, television shows, restaurants, and athletic venues across the state. Notable people from the state include politician and educational advocate William Fulbright; former president Bill Clinton, who also served as the 40th and 42nd governor of Arkansas; general Wesley Clark, former NATO Supreme Allied Commander; Walmart founder and magnate Sam Walton; singer-songwriters Johnny Cash, Charlie Rich, Jimmy Driftwood, and Glen Campbell; actor-filmmaker Billy Bob Thornton; poet C. D. Wright; and physicist William L. McMillan, who was a pioneer in superconductor research.