1. On June 10, 1795, the Treaty of Greenville was signed between the United States and several Native American tribes, including the Wyandot, Delaware, Shawnee, and Miami. The treaty opened up much of present-day Ohio to settlement by Americans.

2. Ohio became the 17th state in the Union on June 10, 1803. The state's name is derived from the Iroquois word for "great river," in reference to the Ohio River which forms its southern boundary.

3. On June 10, 1861, the Battle of Philippi took place in present-day West Virginia (which was then part of Virginia). Although Ohio troops were not directly involved in the battle, it was the first land battle of the Civil War and marked the beginning of the fighting in the Eastern Theater.

4. On June 10, 1880, Ohioan William H. Emery patented the first electric welding process. This invention revolutionized the welding industry by allowing metal to be fused together with heat generated by electrical current rather than by flames.

5. On June 10, 1919, the Treaty of Versailles was presented to the German delegation at the Palace of Versailles in France. Among the American delegates who signed the treaty was Ohio Senator Henry Cabot Lodge, who was a key figure in shaping the treaty's terms. The treaty officially ended World War I and imposed heavy penalties on Germany, setting the stage for the rise of the Nazi party in the 1930s.