The Bonnie Blue Flag, which currently flies over Castle Pinckney, has a long history. The flag was flown as early as 1810 to represent the English-speaking residents of the Republic of West Florida living in parts of Louisiana east of the Mississippi River, who rebelled against Spanish rule and achieved independence. The flag was then adopted on Dec. 10, 1836, by the Congress of the Republic of Texas, and became known as the “Burnet flag.”

When the State of Mississippi seceded from the Union in January 1861, a flag bearing a single star on a blue field was flown from the capitol dome. That same year Harry Macarthy wrote the song, “The Bonnie Blue Flag,” which popularized the flag as a symbol of independence, and gave the flag its current name.

The Bonnie Blue flag flew over Confederate batteries that fired on Fort Sumter on Apr. 12, 1861, and was used as an unofficial flag during the first months of the Civil War. Some southern states, as they seceded, also incorporated a white star on a blue field into their new state flags.