1. On September 17, 1787, delegates from South Carolina joined delegates from other states to sign the United States Constitution in Philadelphia, Pennsylvania. South Carolina's representatives were Charles Pinckney, John Rutledge, and Charles Cotesworth Pinckney.

2. In 1862, Confederate forces under General Robert E. Lee invaded Maryland in an attempt to gain support for the Confederacy from pro-slavery Marylanders. The invasion ultimately failed, and Lee's army retreated back into Virginia. The Battle of Antietam, which took place on September 17, was the bloodiest single day of fighting in American history, with over 23,000 casualties.

3. On September 17, 1916, German U-boats sank the merchant ship Stephano off the coast of South Carolina. The sinking was significant because it marked the first time that a U.S. merchant ship had been sunk by a German sub in World War I.

4. In 1962, South Carolina Governor Donald Russell signed into law the Public Accommodations Act, which prohibited racial discrimination in hotels, motels, and restaurants. The law was one of the first in the South to address segregation in public accommodations.

5. On September 17, 2004, Hurricane Ivan made landfall on the Gulf Coast, causing widespread destruction and flooding in Alabama and Florida. While South Carolina was spared the worst of the storm, it did experience significant rainfall and flooding in some areas.