1. Land Run of 1889: April 23, 1889, marks the date of the Land Run of 1889 when thousands of settlers raced to claim their share of two million acres of unassigned lands in central Oklahoma.
2. Oklahoma City Bombing: On April 23, 1995, Timothy McVeigh rented a Ryder truck that he would later use to carry a bomb that destroyed the Alfred P. Murrah Federal Building in Oklahoma City, killing 168 people.
3. First Oil Well in Oklahoma: On April 23, 1897, the first oil well was struck in Oklahoma, in the town of Bartlesville, marking the beginning of the state’s oil boom.
4. University of Science and Arts of Oklahoma Established: April 23, 1908, marked the founding of the University of Science and Arts of Oklahoma in Chickasha, which remains the state's only public liberal arts institution.
5. Oklahoma Becomes a State: On April 23, 1906, the Oklahoma Territory merged with the Indian Territory to become the state of Oklahoma, making it the 46th state to join the United States.