1. Statehood Day: March 9, 2021 marks South Dakota's 131st Statehood Day, which commemorates the day in 1889 when South Dakota was officially admitted to the Union as the 40th state.

2. Homestake Mine: On March 9, 1876, the Homestake Mine in Lead, South Dakota, was first established by George Hearst. The mine went on to become one of the richest and deepest gold mines in the Western Hemisphere, producing over 40 million ounces of gold over its 125-year history.

3. Sitting Bull Surrenders: On March 9, 1881, legendary Lakota Sioux Chief Sitting Bull surrendered to U.S. military forces at Fort Buford, North Dakota, after five years of resisting encroachment on his people's ancestral lands. He was later transferred to Standing Rock Reservation, where he would live until his death in 1890.

4. Meridian Highway: On March 9, 1915, the Meridian Highway Association was established in Sioux City, Iowa, with the goal of promoting a transcontinental highway that would stretch from Mexico to Canada through 12 U.S. states, including South Dakota. The Meridian Highway eventually became part of U.S. Route 81.

5. Blizzard of 1966: On March 9-10, 1966, a powerful blizzard hit South Dakota, causing widespread damage and disruption. The storm dumped up to 20 inches of snow in some areas, with winds gusting up to 90 miles per hour. Hundreds of motorists were stranded on highways, and many schools and businesses were closed for several days.