1. On January 6, 1890, South Dakota was admitted to the Union as the 40th state. The state had been a territory since 1861, and had a population of 328,808 at the time of statehood.

2. In 1931, on January 6, the South Dakota State Penitentiary in Sioux Falls was destroyed by a fire that killed six inmates. The prison was rebuilt and reopened two years later, and still stands today as part of the South Dakota Department of Corrections.

3. January 6, 1971 is known as the "Sun Dance Day of Prayer" in South Dakota. This day marks the end of the Sun Dance ceremony, an important religious and cultural event for the Lakota and other Native American tribes in the area.

4. On January 6, 1987, a severe winter storm hit South Dakota, with temperatures dropping below zero and wind gusts reaching up to 70 mph. The storm caused widespread power outages and travel disruptions, and was responsible for several deaths and injuries.

5. In 2016, January 6 marked the first day of the 91st legislative session in South Dakota. The session lasted 40 days and saw the passage of several important bills, including ones related to education funding, marijuana legalization, and abortion rights.