When Was Fort Sumter Built. Bombardment of fort sumter, charleston harbor: The attack on fort sumter marked the official beginning of the american civil war—a war that lasted four years, cost the lives of more than 620,000 americans, and freed 3.9 million enslaved people from bondage.

Fort sumter in south carolina was originally built in the nineteenth century as part of the “third system” plan to defend the coasts of america following the war of 1812 against the british. The construction of the fort began in 1829 and was in progress into the beginning of the civil war. Construction began in 1829, and the structure was still being completed in 1861, when the civil war began.