1. Statehood Day: December 6 is celebrated as Statehood Day in Oklahoma, as it marks the date in 1907 when Oklahoma officially became a state in the United States of America.

2. Oklahoma's First Governor: One of the most significant events in Oklahoma's history happened on December 6, 1907, when Charles N. Haskell was inaugurated as the state's first governor. He served from 1907 to 1911 and was a major figure in the early growth and development of Oklahoma.

3. Christmas Pageant of Peace: In 1971, the Christmas Pageant of Peace was held in Oklahoma City on December 6. The event was a major celebration and featured a parade, music performances, and a lighting of the Christmas tree at the State Capitol.

4. Will Rogers Memorial Museum: On December 6, 1938, the Will Rogers Memorial Museum was dedicated in Claremore, Oklahoma. The museum was built in honor of the famous Oklahoma-born humorist and includes a collection of his personal belongings, writings, and artifacts.

5. Oklahoma City Bombing: The Oklahoma City Bombing occurred on April 19, 1995, but the trial of Timothy McVeigh, one of the perpetrators, began on December 6, 1997. The trial lasted for six weeks and resulted in McVeigh being found guilty of 11 counts of murder and sentenced to death.