Fort Sumter is a sea fort located in Charleston Harbor, South Carolina, constructed on an artificial island at the harbor's entrance. Built between 1829 and 1860, the fort is most significant as the site of the first military engagement of the American Civil War. On 12 April 1861, Confederate forces under General P.G.T. Beauregard opened fire on the Union garrison holding the fort, commanded by Major Robert Anderson. Anderson surrendered on 14 April 1861 after a 34-hour bombardment. No Union soldiers died in combat during the battle, though two died in an accidental explosion during a surrender salute. The fort is now administered by the National Park Service as Fort Sumter and Fort Moultrie National Historical Park.

Fort Sumter was named for Thomas Sumter, a South Carolina general of the American Revolutionary War. The fort was designed as part of the Third System of American coastal fortifications - a post-War of 1812 program to defend American harbors - and was intended to mount 135 guns across three tiers, with a garrison of 650 men. Construction was slow and the fort was still incomplete when the secession crisis began in late 1860. When South Carolina declared secession on 20 December 1860, the fort had no permanent garrison. Major Anderson transferred his small Union force from the more exposed Fort Moultrie to Fort Sumter on the night of 26 December 1860, a move that immediately became a focal point of the growing crisis between the incoming Lincoln administration and the Confederate provisional government.

Between January and April 1861, Fort Sumter was a central point of diplomatic and political tension. The Confederate government demanded evacuation; the Lincoln administration sought to resupply the garrison without reinforcing it militarily. Lincoln notified South Carolina's governor on 8 April 1861 that a supply mission carrying only food - not weapons or troops - was en route. Confederate President Jefferson Davis, viewing any continued Union presence as an assertion of federal authority over Confederate territory, ordered Beauregard to demand surrender. Anderson refused. Confederate batteries opened fire at 4:30 a.m. on 12 April 1861. Anderson surrendered the following afternoon and evacuated his garrison on 14 April.

The attack on Fort Sumter is conventionally treated as the opening of the Civil War. Historians differ, however, on questions of causation and responsibility: whether Lincoln's decision to resupply rather than evacuate was a deliberate provocation designed to force the Confederacy to fire first, or a good-faith minimum assertion of federal authority. Similarly, Davis's decision to bombard rather than simply blockade the fort is debated in terms of strategic judgment and political necessity. These interpretive questions bear directly on broader disputes about the war's origins. See Confederate Causation Viewpoint and Union Causation Viewpoint.

The fort was seized by Confederate forces after the battle and remained under Confederate control until February 1865, when Sherman's march through the Carolinas forced its abandonment. Union forces reoccupied Fort Sumter on 17 February 1865. On 14 April 1865 - four years to the day after Anderson's surrender - a flag-raising ceremony was held at the fort. That evening, President Lincoln was shot at Ford's Theatre.

There is broad scholarly consensus on the basic sequence of events at Fort Sumter - the transfer of Union forces, the resupply mission, and the bombardment - though interpretation of motivations and responsibility remains contested among historians. See American Civil War Historiography Consensus.

• Lincoln provoked the attack - Some historians and Southern-sympathetic analysts argue Lincoln engineered the situation to ensure the Confederacy fired first, unifying Northern opinion behind war. See Lincoln Provocation Viewpoint.
• Davis made a strategic blunder - A counterargument holds that Davis's decision to bombard the fort was a political and military error that handed Lincoln a propaganda victory and galvanized Northern support for war. See Davis Error Viewpoint.
• Anderson acted honorably within constraints - Some accounts emphasize Anderson's conduct as a professional soldier caught between loyalty to the Union and personal sympathy for the South. See Anderson Conduct Viewpoint.

• Fort Sumter - History
• Fort Sumter - Debate
• American Civil War
• American Civil War - History
• Secession Crisis
• Confederate States of America

1. United States National Park Service. “Fort Sumter: The First Shot.” Fort Sumter and Fort Moultrie National Historical Park. nps.gov.
2. McPherson, James M. Battle Cry of Freedom: The Civil War Era. Oxford University Press, 1988. pp. 264-275.
3. Current, Richard N. “The Confederates and the First Shot.” Civil War History 7, no. 4 (1961): 357-369.
4. Klein, Maury. Days of Defiance: Sumter, Secession, and the Coming of the Civil War. Alfred A. Knopf, 1997.
5. Detzer, David. Allegiance: Fort Sumter, Charleston, and the Beginning of the Civil War. Harcourt, 2001.