1. On April 16, 1862, the Battle of Shiloh began in Tennessee during the Civil War. Although not in Iowa, many Iowa soldiers fought in this significant battle, including the 18th Iowa Infantry.

2. In 1872, the Iowa State Agricultural Society was formed on April 16. This organization aimed to promote and improve agriculture throughout the state, leading to increased productivity and economic growth.

3. On April 16, 1917, Iowa Governor William L. Harding called out the state militia to prepare for potential involvement in World War I. The Iowa National Guard played a significant role in the war effort, with over 48,000 Iowa soldiers serving during the conflict.

4. In 1962, the Iowa State Fair Board announced plans to construct a new fairgrounds on April 16. This new location in Des Moines would become the current site of the Iowa State Fair, which attracts over 1 million visitors each year.

5. On April 16, 2012, a rare meteorite was discovered in Iowa. The meteorite, known as "Winona," was the first to be found in the state in over 40 years and is estimated to be over 4.5 billion years old. The discovery highlights Iowa's unique geology and the potential for future scientific discoveries in the state.