1. In 1812, Ohio became the 17th state to join the Union. The state was formed out of the Northwest Territory and played a significant role in the Civil War, providing more soldiers per capita than any other state.

2. On May 31, 1889, a massive flood occurred in Johnstown, Pennsylvania, which had a significant impact on Ohio. The flood was caused by the failure of a dam on the Little Conemaugh River, and it resulted in the deaths of over 2,200 people.

3. In 1913, the Great Dayton Flood occurred in Ohio, resulting in the deaths of over 400 people and the destruction of thousands of homes and businesses. The flood was caused by heavy rain and is considered one of the deadliest natural disasters in the country's history.

4. On May 31, 1935, Babe Ruth played his last professional baseball game. Ruth played for the Boston Braves and hit three home runs in the game, marking the end of his legendary career.

5. In 1955, Ohio native James R. Hoffa became the leader of the International Brotherhood of Teamsters. Hoffa was known for his union activities and was eventually imprisoned for fraud and corruption in the 1960s.