The Louisville Museum of Natural History & Science, now known as the Kentucky Science Center, is founded in Louisville.
U.S. & World
April 4 - The first professional baseball league, the National Association, began with a game between the Cleveland Forest Citys and the Fort Wayne Kekiongas. Fort Wayne won with a score of 2 to 0.
October 8 - The Great Chicago Fire began. The deadliest fire in U.S. history also began on the same day in Peshtigo, Wisconsin, eventually killing 1200-2500 people in six counties.