Fort Donelson, a Confederate fort captured on February 16, 1862, by Union forces during the Civil War. The fort was located in Stewart County, Tennessee, on the Cumberland River. In early February a Union army led by General U. S. Grant surrounded the fort while gunboats bombarded it from the river. Munitions, supplies, and 14,000 Confederate troops under General Simon B. Buckner were taken as the fort capitulated to Grant's demand of “unconditional and immediate surrender.”

The fall of Fort Donelson forced the Confederacy to abandon Kentucky and much of Tennessee. Grant became a hero in the North and was promoted to major general. Fort Donelson National Military Park was established in 1928.