1. The first ever Oklahoma State Fair opened on October 18, 1907, in Oklahoma City. The fair drew over 10,000 visitors on the first day and subsequently became an annual event in Oklahoma.

2. Ada Lois Sipuel Fisher, a civil rights pioneer and the first African American to be admitted to the University of Oklahoma's law school, was born on October 18, 1924, in Chickasha, Oklahoma.

3. On October 18, 2011, a 5.6 magnitude earthquake struck near Sparks, Oklahoma, damaging buildings and injuring two people. The earthquake was one of the strongest ever recorded in the state.

4. The Oklahoma City Thunder, a professional basketball team, played their first regular season home game on October 18, 2008, at the Chesapeake Energy Arena. The team, which relocated from Seattle, went on to make the NBA Finals in 2012.

5. The Battle of Shawnee, a skirmish between Confederate and Union forces during the Civil War, took place on October 18, 1861, near Shawnee, Oklahoma. The battle resulted in a Confederate victory and is considered one of the first significant military actions in Oklahoma during the war.