The site for the city was located in an area of Indian Territory that was unassigned to any particular Native American group. Cattle ranchers entered the region, and would-be settlers began to demand that it be opened for settlement. Born of the “Run of '89,” Oklahoma City came into being on April 22, 1889, when approximately 10,000 homesteaders staked land claims near Oklahoma Station (a stop established in 1887 on the Atchison, Topeka and Santa Fe Railway (Atchison, Topeka and Santa Fe Railway Company, The)). A provisional town government was organized at a mass meeting in May 1889, but it was not until May 2, 1890, with the organization of the Oklahoma Territory, that its incorporation became official. While the name Oklahoma City was in popular use from the city's beginning, the U.S. Post Office did not adopt the name until 1923.

Through numerous annexations since 1950, Oklahoma City has become one of the country's largest cities in land area. Its population has grown steadily, surpassing 100,000 in the 1920s and 300,000 in the 1950s. People of European ancestry have constituted the great majority of the population since the early days, although their proportion has slowly declined. African Americans constitute about one-seventh and Hispanics an increasing one-tenth of the total. There are also small but significant communities of Native Americans and Asians.

Oklahoma City has become one of the nation's foremost aviation centres, Tinker Air Force Base (a large logistics and communications base just southeast of the city) and the Federal Aviation Administration's Mike Monroney Aeronautical Center for training in air safety and aviation technology (Oklahoma City) being major installations. The city's highly diversified manufactures include petroleum products, executive aircraft, industrial machinery, electronics, automobiles, automotive parts, tires, computer equipment, and chemicals. Services, especially government, are a major part of the economy; health care, education, tourism, and customer service operations are also important. Oklahoma City is a distribution centre, particularly for food, and area farms produce cattle and wheat. Stockyards City (Oklahoma City) was founded in 1910 as a livestock market and meat-processing centre; although meatpacking ended in the early 1960s, Stockyards City remained one of the world's largest cattle markets into the 21st century. Many original businesses continue to provide services and supplies for farmers, ranchers, and cowboys.

Oklahoma City University was founded in 1904, Oklahoma State University–Oklahoma City in 1961, and Oklahoma City Community College in 1969. The Health Sciences Center of the University of Oklahoma (Oklahoma, University of) is also in the city, and several other institutions of higher education are in the metropolitan area.

Oklahoma City is the home of the National Cowboy and Western Heritage Museum and the National Softball Hall of Fame and Museum. The Oklahoma State Museum of History has an outstanding collection of Native American artifacts. The Oklahoma State Fair is held in the city each September, and State Fair Park is the scene of the International Finals Rodeo in January. Other annual events include the Red Earth Festival (Native American culture; June), a bluegrass festival in nearby Guthrie (October), and several horse shows.