1. On October 21, 1861, the Battle of Ball's Bluff took place in Virginia, but it had a significant impact on Indiana. The battle resulted in the death of Colonel Edward D. Baker, who was a close friend of President Abraham Lincoln and a former U.S. Senator from Oregon. He was also the commanding officer of the 1st California Brigade, which included the 1st Indiana Cavalry Regiment.

2. On October 21, 1887, the State Board of Health of Indiana was established. This organization was responsible for promoting and enforcing public health laws and regulations in Indiana. It was the first such organization in the United States, and it became a model for other states.

3. On October 21, 1901, the Indianapolis Streetcar Strike began. The strike lasted for six weeks and was one of the most violent labor disputes in Indiana history. During the strike, violence erupted between striking workers and police officers, resulting in several deaths and injuries.

4. On October 21, 1949, the Indiana University School of Nursing was established. This school has trained thousands of nurses over the years and is considered one of the top nursing schools in the country.

5. On October 21, 1988, the Indiana Pacers played their first game at the newly-built Market Square Arena. The Pacers defeated the Miami Heat 116-113 in front of a sellout crowd. The arena was the home of the Pacers for over 20 years until it was replaced by Bankers Life Fieldhouse in 1999.