1. In 1868, the Battle of Badlands took place in South Dakota between the U.S. Army and the Sioux tribe. The battle resulted in a defeat for the Sioux and led to the Treaty of Fort Laramie.

2. On October 15, 1917, the town of Aberdeen became the first city in South Dakota to have a municipal airport. The airport was initially used for crop dusting and mail delivery and later for commercial flights.

3. The famous artist, Harvey Dunn, was born on October 15, 1884, in Manchester, South Dakota. Dunn was known for his paintings of life on the prairies and his illustrations for magazines like The Saturday Evening Post.

4. The Black Hills National Forest was established on October 15, 1897, by President William McKinley. The forest covers more than 1.2 million acres in western South Dakota and includes popular attractions like Mount Rushmore.

5. In 1962, the Minuteman Missile Site was activated near Wall, South Dakota. The site was one of several that housed nuclear missiles during the Cold War and is now a National Park Service site that provides tours and educational exhibits about the Cold War era.