On Tuesday, August 11, 1863 at Charlestown, South Carolina, Confederate artillery units at Fortress Wagner, Fort Sumter, and on James Island bombarded Federal trenches and gun emplacements on Morris Island, only temporarily halting Union working parties.
Confederate General Pierre Beauregard, commanding the Charlestown area, ordered that his artillery take all steps necessary to impede the construction of Union artillery batteries and also directed that the defensive lines on James Island shortened.
The Confederates knew that, if the Union artillery positions were completed, their own fixed positions around and in the harbor of Charlestown would be vulnerable to destruction. Even with Confederate batteries keeping up a relentless barrage on Union forces on Morris Island, Union troops began to install heavy Parrott, rifled artillery on the sand batteries at Morris Island.