On January 9, 1861, the Convention of the People of Mississippi held a referendum and legally seceded from the United States. With this announcement to the world, a large blue flag bearing a single white star was raised over the capitol building in Jackson, Mississippi. One of the witnesses to this event, an Irish-born actor named Harry McCarthy, was so inspired by the spectacle that he wrote a song entitled “The Bonnie Blue Flag,” which soon became the second most popular patriotic song in the Confederacy.

But the Bonnie Blue Flag didn’t begin there. It was also used as a symbol of sovereignty and independence throughout the South before the War, dating as far back as 1810: