1. South Dakota was admitted as the 40th state in the Union on November 23, 1889. This day marks an important milestone in the state's history as it became a full-fledged member of the United States.

2. On November 23, 1915, the famous geologist James Hutton Boss discovered a prehistoric dinosaur fossil in the Black Hills of South Dakota. The fossil was identified as a Stegosaurus and is now on display at the Black Hills Institute of Geological Research in Hill City.

3. In 1943, the Corn Palace in Mitchell, South Dakota, was hit by a tornado on November 23. Despite the damage, the palace was quickly repaired and continues to be a popular tourist attraction in the state.

4. On November 23, 1972, the Oglala Sioux tribal council declared a state of emergency on the Pine Ridge Reservation due to the high levels of poverty and unemployment in the area. This declaration brought national attention to the struggles of Native Americans in South Dakota and led to increased efforts for economic development and tribal sovereignty.

5. In 1999, the Crazy Horse Memorial in Custer County, South Dakota, unveiled their completed carving of the face of Crazy Horse on November 23. The memorial, which is still under construction, is being built to honor the Lakota warrior and advocate for Native American rights.