The Battle of Fort Henry was fought February 6, 1862, in western Tennessee, during the American Civil War. It was the first important victory for the Union and Brig. Gen. Ulysses S. Grant in the Western Theater.
On February 4 and February 5, Grant landed two divisions just north of Fort Henry on the Tennessee River. His plan was to advance upon the fort on February 6 while it was being simultaneously attacked by U.S. Navy gunboats commanded by Flag Officer Andrew Hull Foote. A combination of effective naval gunfire and poor siting of the fort, almost completely inundated by rising river waters, caused its commander, Brig. Gen. Lloyd Tilghman, to surrender to Foote before the Army arrived.
The surrender of Fort Henry opened the Tennessee River to Union traffic past the Alabama border, which was demonstrated by a "timberclad" raid of wooden ships from February 6 through February 12, which destroyed Confederate shipping and railroad bridges. Grant's army proceeded overland 12 miles to the bloody Battle of Fort Donelson.

Background
Fort Henry was a five-sided, open-bastioned earthen structure covering 10 acres on the eastern bank of the Tennessee River, near Kirkman's Old Landing and Standing Rock Creek, nearly opposite the mouth of the Sandy River.

Battle
After the battle had lasted 75 minutes, Tilghman surrendered to the fleet, which had engaged the fort and closed within 400 yards. A small boat from the fleet was able to sail directly through the sally port of the fort and pick up Tilghman for the surrender ceremony on Cincinnati, demonstrating the extent of flooding. Twelve officers and 82 men surrendered; other casualties are estimated to be 15 men killed and 20 wounded. The evacuating force left all of its artillery and equipment behind. Tilghman was imprisoned, but exchanged on August 15.

Preservation

Cooling, Benjamin Franklin, The Campaign for Fort Donelson, U.S. National Park Service and Eastern National, 1999, ISBN 1-888213-50-7.
Eicher, David J., The Longest Night: A Military History of the Civil War, Simon & Schuster, 2001, ISBN 0-684-84944-5.
Esposito, Vincent J., West Point Atlas of American Wars, Frederick A. Praeger, 1959.
Gott, Kendall D., Where the South Lost the War: An Analysis of the Fort Henry—Fort Donelson Campaign, February 1862, Stackpole books, 2003, ISBN 0-8117-0049-6.
McPherson, James M., Battle Cry of Freedom: The Civil War Era (Oxford History of the United States), Oxford University Press, 1988, ISBN 0-19-503863-0.
Nevin, David, and the Editors of Time-Life Books, The Road to Shiloh: Early Battles in the West, Time-Life Books, 1983, ISBN 0-8094-4716-9.
Woodworth, Steven E., Nothing but Victory: The Army of the Tennessee, 1861 – 1865, Alfred A. Knopf, 2005, ISBN 0-375-41218-2.
National Park Service battle description