The Bonnie Blue Flag was an unofficial banner of the Confederate States of America at the start of the American Civil War in 1861. It consists of a single, five-pointed white star on a blue field. It closely resembles the flag of the short-lived Republic of West Florida of 1810.
When the state of Mississippi seceded from the Union in January 1861, a flag bearing a single white star on a blue field was flown from the capitol dome. Harry Macarthy helped popularize this flag as a symbol of the Confederacy by writing the words to the popular song "The Bonnie Blue Flag" early in 1861. Some seceding southern states incorporated the motif of a white star on a blue field into new state flags.
Although the name "Bonnie Blue" dates only from 1861, several authors have claimed that the Civil War flag is identical with the banner of the Republic of West Florida, which broke away from Spanish West Florida in September 1810 and was annexed by the United States 90 days later. In 2006 the state of Louisiana formally linked the name "Bonnie Blue" to the West Florida banner by passing a law designating the Bonnie Blue Flag as "the official flag of the Republic of West Florida Historic Region".
In 2007 one of six known Bonnie Blue flags from the Civil War era was sold at auction for $47,800. The flag had been carried by the Confederate 3rd Texas Cavalry and later exhibited as part of the 1936 Texas Centennial Exposition.