Recurrence pattern: every year on November 30.

National Mississippi Day is observed worldwide every November 30 to recognize Mississippi as the 20th state to join the Union. Established by National Day Calendar as part of its National State Days project, the day celebrates the state's rich history, which includes its name derived from the Mississippi River, meaning "great river" in the Ojibwe language. The territory was originally inhabited by Native American tribes and later became a focal point of European colonization, with claims from Spain, France, and Britain before becoming part of the United States. Mississippi was officially admitted to the Union on December 10, 1817, following significant population growth due to cotton cultivation. The day serves as a reminder of the state's cultural significance, often referred to as the Magnolia State and known for its contributions to music. National Mississippi Day is not recognized in any official capacity but highlights the state's heritage and historical milestones.