1. On August 15, 1836, the Kentucky State Medical Society was founded in Louisville. At the time, there was great concern over the lack of medical education and regulation in the state, and the society was formed in order to promote the improvement of medical knowledge and practice.

2. The Battle of Mill Springs, a significant Civil War engagement in Kentucky, took place on January 19-20, 1862. However, August 15 is recognized as the "anniversary of the anniversary" of the battle, as it was on that day in 1910 that the Mill Springs Battlefield Association was founded to preserve the site of the battle for future generations.

3. On August 15, 1936, the Ohio River Flood peaked in Kentucky, causing widespread devastation and loss of life. The flood was the result of record-breaking rainfall in the Ohio River Basin, and it affected more than a dozen states. In Kentucky, over 100 people were killed, and thousands were left homeless.

4. August 15, 1951, marked the opening of Kentucky's first ever state park, Natural Bridge State Resort Park. The park is known for its unique geological formations, including the titular natural bridge, which is a sandstone arch that spans 78 feet. The park is a popular destination for hiking, camping, and other outdoor activities.

5. On August 15, 1977, the Bluegrass Army Depot in Madison County, Kentucky, was the site of an explosion that resulted in the release of chemical weapons. The incident, which occurred during a weapons disposal operation, led to the evacuation of thousands of people from the surrounding area. No one was killed in the explosion, but several workers were injured. The incident raised concerns about the safety of chemical weapons disposal, and led to increased scrutiny of the Bluegrass Army Depot and other facilities that store or dispose of such weapons.