The Union blockade of the Georgia coast during the U.S. Civil War revolved around preventing supplies from being delivered to the port of Savannah, according to New Georgia Encyclopedia. The city was the most significant port in Georgia, and the Union strategy centered on securing bases around outlying islands to deny access to private merchants and mercenary ships.
Before the full blockade was implemented, Confederate privateer Edward C. Anderson ran the Union blockade several times, starting in November 1861. The Union realized they needed to strengthen the blockade further to prevent smaller ships from getting into port. Securing Brunswick and St. Simons Island helped keep larger ships away. Small ships able to slip through did not bring enough supplies to help the Confederate cause.
A small fleet of seven Confederate gunboats, three of them ironclad, were no match for the Union Navy. Despite unique weapons, like the torpedo, Union forces maintained a stranglehold on the Savannah coast. A small victory came in June 1864 with the capture of the U.S.S. Water Witch while it was docked.
Georgians could only hold out for a limited amount of time. Union Gen. William T. Sherman's troops assaulted Fort McAllister in December 1864 and captured Savannah Dec. 22, 1864, thereby linking up with the Union Navy and ending the blockade.