Official and Traditional Colors of South Carolina

The South Carolina State Flag Study Committee's determination of Pantone 282 C as the official indigo shade represents one of the most scientifically rigorous state color determinations in American history. The committee worked with Dr. Emerson of the South Carolina Department of Archives and History to locate surviving Revolutionary War artifacts, ultimately finding two surviving cap badges from Moultrie's 2nd South Carolina Regiment at Old Jacksonboro and Fort Johnson on James Island. A regimental flag from 1776, purchased by the National Museum of American History (Smithsonian) in 1989, also informed the color analysis. Pantone 282 C Coated was approved as both a visual reference and a spectrophotometric standard, with the committee noting that 'a spectral reference curve may be constructed from sample data measured in 10nm intervals' for objective comparisons.

The connection between indigo blue and South Carolina runs deeper than military history. Eliza Lucas Pinckney, a planter's daughter, successfully cultivated indigo (Indigofera tinctoria) in South Carolina's lowcountry beginning in 1744, developing the crop into one of the colony's most valuable exports. By the 1770s, South Carolina was exporting over 1.1 million pounds of indigo annually to Britain, making it the principal supplier of indigo dye for the British textile industry. The indigo trade — which also enabled the blue uniform color of Moultrie's soldiers — thus contributed both economically and visually to the Revolutionary War, creating a remarkable loop of history in which South Carolina's own export product colored the uniforms that inspired the state's defining official color.

The Battle of Sullivan's Island was one of the most consequential American victories of the Revolutionary War. A British fleet under Admiral Peter Parker attacked Fort Moultrie, the palmetto-log fort guarding Charleston Harbor, with a squadron of warships on June 28, 1776. The soft palmetto wood of the fort's walls proved uniquely effective at absorbing cannon fire — unlike the stone and brick of conventional forts — and the fort held through a sixteen-hour bombardment. At one point during the battle, a cannon shot knocked the flag from its staff. Sergeant William Jasper ran into the open fire, retrieved the flag, and raised it again on his lance — rallying the troops and becoming one of the Revolution's most celebrated acts of individual heroism. Charleston was saved from British occupation for four more years.

Colonel William Moultrie's decision to base the South Carolina flag on the color of his regiment's uniforms was practical as well as symbolic — the flag needed to be instantly identifiable in the confusion of battle as belonging to South Carolina's forces. The blue he chose was indigo blue, the most available deep blue dye in colonial South Carolina precisely because of the thriving indigo cultivation industry that Eliza Lucas Pinckney had established three decades earlier. The crescent on the flag — taken from the silver gorget insignia worn on the front of the soldiers' caps — completed a design that would endure with minimal changes from 1775 through the present day, a period of 250 years.