Battery Thompson Gun Placement #2 - Fort Moultrie, Sullivan's Island, near Charleston, South Carolina - June 18, 1984.

Battery Thomson, constructed 1906-1909 by Captain G.P. Howell, is one of a series of batteries extending from Fort Moultrie on the west to the eastern end of Sullivan’s Island. Charleston Harbor has always had some form of fixed harbor defense beginning with Fort Johnson in 1708 and culminating with the construction of these batteries in the fortification of Sullivan’s Island at the mouth of Charleston Harbor. This two, 10 inch gun, coastal defense battery was established in order to command the entrance to the Charleston harbor jetties. It was constructed following the recommendations of the Endicott Board under the Cleveland Administration. The battery, approximately 326 feet long and 84 feet wide, consists of two sections: The glacis and the armament complex. The glacis, a relatively smooth, slightly sloping area on the sides and front of the battery, protects the armament complex from bombardment. The armament complex consists of two recessed disappearing gun platforms, the loading platforms, ammunition hoists (one per gun), and observation post and various staircases and ramps for access. The ocean side of the battery is approximately 10 feet high. Walls and ceilings are of concrete. All machinery and guns were removed in 1947 at the decommissioning of the battery. Listed in the National Register June 25, 1974.

The American Civil War (1861–1865) was a civil war between the United States of America (the "Union") and the Southern slave states of the newly-formed Confederate States of America under Jefferson Davis. The Union included all of the free states and the five slaveholding border states and was led by Abraham Lincoln and the Republican Party. Republicans opposed the expansion of slavery into territories owned by the United States, and their victory in the presidential election of 1860 resulted in seven Southern states declaring their secession from the Union even before Lincoln took office. The Union rejected secession, regarding it as rebellion.

Hostilities began on April 12, 1861, when Confederate forces attacked a U.S. military installation at Fort Sumter in South Carolina. Lincoln responded by calling for a large volunteer army, then four more Southern states declared their secession. In the war's first year, the Union assumed control of the border states and established a naval blockade as both sides massed armies and resources. In 1862, battles such as Shiloh and Antietam caused massive casualties unprecedented in U.S. military history. In September 1862, Lincoln's Emancipation Proclamation made ending slavery in the South a war goal, which complicated the Confederacy's manpower shortages.

In the East, Confederate commander Robert E. Lee won a series of victories over Union armies, but Lee's reverse at Gettysburg in early July, 1863 proved the turning point. The capture of Vicksburg and Port Hudson by Ulysses S. Grant completed Union control of the Mississippi River. Grant fought bloody battles of attrition with Lee in 1864, forcing Lee to defend the Confederate capital at Richmond, Virginia. Union general William Sherman captured Atlanta, Georgia, and began his famous March to the Sea, devastating a hundred-mile-wide swath of Georgia. Confederate resistance collapsed after Lee surrendered to Grant at Appomattox Court House in April 1865.

The war, the deadliest in American history, caused 620,000 soldier deaths and an undetermined number of civilian casualties, ended slavery in the United States, restored the Union by settling the issues of nullification and secession and strengthened the role of the Federal government. However, issues affected by the war's unresolved social, political, economic and racial tensions continue to shape contemporary American thought.