Charleston South Carolina, was a hotbed of secession at the start of the American Civil War, and an important Atlantic Ocean port city for the fledgling Confederate States of America. The first shots of the Civil War were fired at a Federal ship entering Charleston Harbor. Later, the bombardment of Fort Sumter triggered a massive call for Federal troops to put down the rebellion. The city and its surrounding fortifications were repeatedly targeted by the Union Army and Navy. So were many other port cities, it had become a major port for blockade running. It was 22nd largest city according to the 1860 Census from the Union. The city was fortified with batteries and forts to protect itself for fear of a Union invasion. Upon the secession of South Carolina, the first state to secede, these areas were seized by the Confederacy. It was a major port in the Confederacy.