Oklahoma historical timeline

Long before European contact, the Spiro Mounds complex in eastern Oklahoma was a major center of Mississippian culture, flourishing between roughly AD 850 and 1450. The Coronado Expedition, led by a Spanish conquistador, crossed the region in 1541; French colonists later claimed it until the United States acquired the land west of the Mississippi in the 1803 Louisiana Purchase. Through the 1830s, the federal government forced the Cherokee, Muscogee, Seminole, Chickasaw and Choctaw nations, the so-called "Five Civilized Tribes," from their homelands in the southeastern United States onto this land, then designated Indian Territory, along the deadly journey now called the Trail of Tears; the Choctaw were removed first, in 1831, and the Cherokee last, in 1838.

Cattle drives from Texas crossed Indian Territory through the late 19th century before the Dawes Act of 1887 began breaking up tribal landholdings. On 22 April 1889, at high noon, an estimated 50,000 settlers rushed to claim land in the Land Run, founding what became Oklahoma City the same day; Oklahoma entered the United States in 1907. Oil discovered under Oklahoma City in 1928, and decades earlier in Tulsa, built both cities' early 20th-century wealth, but that same period brought the 1921 Tulsa race massacre, when white mobs destroyed the prosperous Greenwood District, known as "Black Wall Street," over two days in late May and early June. The 1930s Dust Bowl, a severe, human-worsened drought, devastated the state's agriculture and drove thousands of Oklahomans, memorialized in Woody Guthrie's songs, to migrate west. On 19 April 1995, the bombing of the Alfred P. Murrah Federal Building in Oklahoma City by domestic terrorists killed 168 people, the deadliest act of domestic terrorism in U.S. history, and is remembered today at the Oklahoma City National Memorial.