1. In 1973, the National Cowboy Hall of Fame and Western Heritage Center officially opened in Oklahoma City. The museum focuses on the history and culture of the American West and honors those who played a vital role in shaping it.

2. On June 9, 1953, the town of El Reno was hit by a massive tornado that destroyed much of the downtown area and killed 13 people. It was one of the deadliest tornadoes in Oklahoma history and served as a wake-up call for better storm warning systems in the state.

3. In 1910, the first oil well was drilled in what is now known as the Greater Seminole Area in eastern Oklahoma. It marked the beginning of the oil boom in Oklahoma, which played a significant role in the state's economic growth.

4. On June 9, 1868, the Battle of Washita River took place near present-day Cheyenne, Oklahoma. Led by General George Armstrong Custer, the U.S. Army attacked and killed over 100 Cheyenne men, women, and children, marking a significant victory for the United States during its ongoing conflict with Native American tribes.

5. Oklahoma State University was founded on June 9, 1890, as the Oklahoma Agricultural and Mechanical College. It has since grown into a major research institution with campuses in Stillwater, Tulsa, and Oklahoma City, serving thousands of students each year.