It's one of the most daring escapes of the Civil War: a band of black slaves commandeer a Confederate steamship at night, navigate through Southern defenses, then run for freedom to the Union blockade of Charleston Harbor.

That remarkable tale is now coming back to life with the discovery of the wreck of the steamship Planter off the South Carolina coastline.

Marine archaeologists with the National Oceanic and Atmospheric Administration announced the ship's location Tuesday, 152 years after Robert Smalls sailed the Planter, eight crew members and their families out of slavery. It's the culmination of a six-year search for the sidewheel steamship using historic records, side-scan sonar and ground-penetrating magnetometers.

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NOAA officials say the underwater search has engaged students about the history of the Civil War and the contribution of African-American slaves as seamen during the early years of the United States.

"Robert Smalls stands out as a figure of history," said Michael Cottman, president of the National Association of Black Scuba Divers. "The symbolism is important and will resonate with people."

The Planter was a Canadian cargo ship and crew transport that was leased to the Confederate Navy when the war broke out in early 1862. Smalls had worked as a steersman on the ship, learning the underwater topography of the harbor and its backwaters, according to Bruce Terrell, an archaeologist and historian for NOAA's Office of Marine Sanctuaries.

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"The captain would tell him where to go, and Smalls' knowledge became vital to the Confederates," Terrell said.

On the night of May 12, 1862, the white officers of the Planter debarked to attend a ball in Charleston, leaving eight black crew members on board. Planter hatched his plan, sailing to a nearby wharf to pick up several families and then sailing out to sea. Smalls wore the straw hat of a captain and wasn’t noticed by guards at the harbor entrance, Terrell said.

The Steamship Planter.Harper's Weekly, May 1862

Smalls then raised a white shirt or tablecloth as a sign of surrender to the Union ships blockading Charleston Harbor. The commanding admiral was so impressed with the escapade that they offered Smalls a job as pilot of the Planter, which was turned over the Union Army as a transport.

Smalls became a cause célèbre in the North, and was tapped to recruit black slaves to form units to fight against the Confederacy. He eventually was elected to Congress. After the war, Smalls and the Planter were well known among local African Americans. As the Planter's captain, he transported many freed slaves to newly created farm communities at Hilton Head and Port Royal.

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The Planter returned to service as a cotton cargo hauler along the South Carolina coast. It ran aground off Cape Romain in 1876 during a salvage operation and in time, its exact location became forgotten.

NOAA officials resurrected the Planter search in 2008. Underwater archaeologists believed they found the ship in 2010 in 12 feet of water and 10 feet of sand in Cape Romain National Wildlife Refuge. Because the ship lies inside an important sea turtle breeding area, it’s not likely that it will be salvaged.

NOAA and NABS put together this website about the history of Smalls, the Planter and other ships during the slave era.