1. On December 21, 1987, a severe ice storm hit South Dakota, causing widespread damage and leaving thousands of residents without power. The storm lasted for several days and resulted in millions of dollars in damage.

2. In 1890, the Wounded Knee Massacre occurred on December 21. The U.S. Army killed over 150 Lakota Sioux, most of whom were women and children, in one of the most significant and tragic events in South Dakota history.

3. On December 21, 1918, South Dakota became the first state in the United States to ratify the 18th Amendment, which prohibited the sale, transportation, and manufacture of alcohol.

4. In 1892, the South Dakota Agricultural College (now South Dakota State University) was founded on December 21. Today, the university is one of the state's largest institutions of higher education and is known for its expertise in agriculture and engineering.

5. On December 21, 1988, a devastating fire destroyed the hotel at the Deadwood Mountain Grand resort in Deadwood, South Dakota. The fire caused millions of dollars in damage, but the historic building was later restored and reopened as a popular destination for tourists and locals alike.