1. On October 20, 1864, the Battle of Cedar Creek took place in Virginia, which included the participation of several South Carolina-based regiments on both sides. The Confederate forces, including the South Carolina Brigades, experienced a significant defeat against Union forces.

2. On this day in 1944, Charleston-based marine private Jim Robinson was posthumously awarded the Medal of Honor for his bravery in the Battle of Peleliu in the Pacific Theater of World War II. Robinson was killed while single-handedly defending his platoon from an enemy counterattack.

3. In 1955, the South Carolina Lutheran Synod became a founding member of the Lutheran Church in America. This organization was the result of the merger between several Lutheran denominations and served as a significant milestone in the history of Lutheranism in South Carolina.

4. October 20, 1956, saw the opening of the Lake Murray Dam, which created a massive reservoir in Lexington County. The dam was built to control flooding in the Saluda River and provided a crucial water supply for the city of Columbia.

5. On this day in 1976, the Space Shuttle Enterprise completed its first free-flight test, marking a significant step forward in the development of the Space Shuttle program. The Enterprise was built at the NASA facility in North Charleston, South Carolina, and would go on to perform several critical flights in the years to come.