“A detailed, authoritative, and expansive new study of the centerpiece of Charleston’s defensive network.” ? Pat Brennan, co-author of Gettysburg in Color Fort Sumter. Charleston. April 1861. The start of the Civil War. The bombardment and surrender of Sumter were only the beginning of the story. Both sides understood the military significance of the fort and the busy seaport, which played host to one of the longest and most complicated and fascinating campaigns of the entire Civil War. Richard Hatcher’s Thunder in the Harbor: Fort Sumter and the Civil War is the first modern study to document the fort from its origins, through the war, and up to its transfer to the National Park Service in 1948. After its surrender, Southern troops immediately occupied and improved Sumter’s defenses. The U. S. blockaded Charleston Harbor and for two years the fort, with its 84 heavy guns and a 500-man garrison, remained mostly untested. That changed in July 1863 when a powerful combined operation set its sights on the fort, Charleston, and its outer defenses. The result was a grueling 22-month land and sea siege—the longest of the Civil War. The complex effort included ironclad attacks, land assaults, raiding parties, and siege operations.