1. On December 20, 1905, the state of Oklahoma passed a new law that declared Oklahoma City as the official capital of the state. This decision had been hotly debated, with some citizens pushing for the capital to be located in Guthrie. However, Oklahoma City won out and has remained the state capital ever since.

2. December 20, 1929 saw the opening of the First National Bank of Muskogee, which was the first federally-chartered bank in Oklahoma to have a female president. Sallie Lee Crain was appointed as the president of the bank, making her one of the first female bank presidents in the United States.

3. The first documented tornado in Oklahoma during December occurred on December 20, 1957. The twister struck just outside of Enid, causing extensive damage to homes and businesses. Thankfully, no one was killed in the storm, but several people were injured.

4. In 1973, legendary astronaut and Oklahoman Thomas Stafford was the commander of the Apollo 18 space mission. The spacecraft launched on December 20, 1972, and was the second manned mission to land on the Moon. The mission was a huge success and marked the end of the Apollo program.

5. On December 20, 2012, the Oklahoma City Thunder defeated the Minnesota Timberwolves by a score of 106-84. The victory marked the Thunder's 12th straight win of the season, which was a franchise record at the time. The Thunder would go on to reach the NBA Finals that year, but were defeated by the Miami Heat.