<P> As many Southern port cities had been closed off by the Union blockade, Charleston became an important center for blockade running . Repeated attempts by the Union Navy to take Charleston and / or batter its defenses into the ground proved fruitless, including the Stone Fleet . The city resisted military occupation for the majority of the war's four years . </P> <P> In 1863, the Union began an offensive campaign against the defenses of Charleston Harbor, beginning with a combined sea - land engagement . The naval bombardment accomplished little however, and the land forces were never put ashore . By summer of 1863, the Union turned its attention to Battery Wagner on Morris Island, which guarded the harbor entrance from the southwest . In the First and Second battles of Fort Wagner, Union forces suffered heavy losses in a failed attempt to capture the fort . A siege however resulted in Confederate abandonment of Fort Wagner by September of that year . An attempt to recapture Fort Sumter by a naval raiding party also failed badly, but Ft . Sumter was gradually reduced to rubble via bombardment from shore batteries, after the capture of Morris Island . </P> <P> With the development of newer, longer - range artillery, and as Union forces were able to place batteries even closer to the city . In November 1863, Jefferson Davis visited the city and noted it was better the city be reduced to "a heap of ruins" than surrender . The bombardment that began in late 1863 continued on and off for 587 days . This bombardment would destroy much of the city that had survived the fire . A coordinated series of attacks on the city were launched in early July 1864, including an amphibious assault on Fort Johnson and an invasion of Johns Island . These attacks failed, but they continued to wear down the city's defenders . The defenders were finally beaten back and the Union was able to capture the city, only a month and a half before the war ended . </P> <P> Charleston Harbor was also the site of the first successful submarine attack in history on February 17, 1864, when the H.L. Hunley made a daring night attack on the USS Housatonic . Although the Hunley survived the attack, she foundered and sank while returning from her mission, thus ending the threat to the Union blockade . </P>

How was the city of charleston affected by the civil war