1825    The U.S. Congress approves Indian Territory (in what is present-day Oklahoma), clearing the way for forced relocation of the Eastern Indians on the "Trail of Tears".

1842    Indian Wars: Second Seminole War ends, with the Seminoles forced from Florida to Oklahoma.

1850    The Compromise of 1850 transfers a third of Texas's claimed territory (now parts of Colorado, Kansas, New Mexico, Oklahoma, and Wyoming) to federal control in return for the U.S. federal government assuming $10 million of Texas's pre-annexation debt.

1893    Settlers race in Oklahoma for prime land in the Cherokee Strip.

1901    Kiowa land in Oklahoma is opened for white settlement, effectively dissolving the contiguous reservation.

1907    Indian Territory and Oklahoma Territory become Oklahoma and are admitted as the 46th U.S. state.

1915    The U.S. Supreme Court hands down its decision in ''Guinn v. United States'' 238 US 347 1915, striking down an Oklahoma law denying the right to vote to some citizens.

1935    The world's first parking meter is installed in Oklahoma City, Oklahoma.

1947    The Glazier-Higgins-Woodward tornadoes kill 181 and injure 970 in Texas, Oklahoma, and Kansas.

1948    The first successful tornado forecast predicts that a tornado will strike Tinker Air Force Base, Oklahoma.

1951    The "Johnny Bright Incident" occurs in Stillwater, Oklahoma

1995    Oklahoma City bombing: The Alfred P. Murrah Federal Building in Oklahoma City, Oklahoma, USA, is bombed, killing 168. That same day convicted murderer Richard Wayne Snell, who had ties to one of the bombers, Timothy McVeigh, is executed in Arkansas.

2008    An EF4 tornado strikes the Oklahoma-Kansas state line, killing 21 people and injuring over 100.