1. In 1921, the Tulsa race massacre, considered one of the deadliest incidents of racial violence in U.S. history, occurred on June 25th. Over the course of two days, a white mob attacked and destroyed the affluent Black neighborhood of Greenwood, killing an estimated 300 people and injuring hundreds more.

2. On June 25, 1900, Oklahoma Territory's delegate to Congress, Dennis Flynn, successfully introduced legislation to establish the University of Oklahoma. OU opened in 1903 in Norman, Oklahoma, and today it is one of the state's largest universities with over 30,000 students.

3. Cherokee Nation Chief Wilma Mankiller was re-elected for her second term on June 25, 1987, becoming the first woman to hold the position. Mankiller's tenure was marked by her efforts to improve healthcare, education, and economic development for the Cherokee Nation.

4. June 25, 1962, marked the opening of Will Rogers World Airport in Oklahoma City. Originally named Oklahoma City Municipal Airport, it was renamed in honor of Oklahoma-born humorist and actor Will Rogers. Today, the airport serves over 4 million passengers a year.

5. Professional basketball player Blake Griffin was born in Oklahoma City on June 25, 1989. Griffin played for the University of Oklahoma before being drafted by the Los Angeles Clippers in 2009. He went on to win the NBA Rookie of the Year award and has been named to multiple All-Star teams.