Overview
After capturing Fort Henry on February 6, 1862, General Ulysses S. Grant turned toward Fort Donelson, which protected the Cumberland River. Grant marched his army 12 miles and placed his troops in a semicircle around the fort’s western side. Reinforcements increased the Union force to about 25,000 soldiers, while General John B. Floyd commanded the Confederate garrison.
On February 14, Flag Officer Andrew Hull Foote’s gunboats attacked Fort Donelson from the Cumberland River. The bombardment failed because Confederate artillery occupied higher ground and forced the gunboats to withdraw.
Confederate forces attempted to escape on February 15 by attacking the Union right flank under General John McClernand. They forced his troops backward but did not defeat them. Although an escape route remained open, General Gideon Pillow ordered his soldiers back to their trenches for supplies. Grant then launched a counterattack that forced the Confederates back into defensive positions.
That night, Floyd and Pillow transferred command to General Simon B. Buckner and escaped. On February 16, Buckner requested surrender terms. Grant demanded “unconditional and immediate surrender,” and Buckner accepted. The victory opened the Cumberland River to Union invasion, forced Confederate forces deeper into Tennessee, and made Grant a national military figure.
Essential Facts
- Date: February 12–16, 1862.
- Location: Fort Donelson, Stewart County, Tennessee.
- Participants: The United States of America (USA) and the Confederate States of America (CSA).
- USA Commanders: Ulysses S. Grant and Andrew Hull Foote.
- CSA Commanders: John B. Floyd, Gideon J. Pillow, and Simon B. Buckner.
- Who Won: The United States won the Battle of Fort Donelson.
- Campaign: Federal Penetration Up the Cumberland and Tennessee Rivers.
- Era: Civil War, January–June, 1862.
Statistics
United States of America
- Casualties: 2,691 killed, wounded, missing or captured, including 507 killed.
- Forces Engaged: Army of the Tennessee and Western Flotilla.
- Troop Strength: Roughly 25,000.
Confederate States of America
- Casualties: 13,846 killed, wounded, missing, or captured, including 327 killed.
- Forces Engaged: Army of Central Kentucky and Fort Henry Garrison.
- Troop Strength: Roughly 16,000.
Significance
The Battle of Fort Donelson was important to American History because it helped open the Tennessee and Cumberland rivers as routes for Union invasions into the South. The Confederate defeat forced military forces to abandon operations in Kentucky and withdraw deeper into Tennessee. The victory also raised morale in the North. Grant’s demand for “unconditional and immediate surrender” earned him the nickname “Unconditional Surrender” Grant, made him a national celebrity, and led to his promotion to Major General of Volunteers.
History
At the onset of the American Civil War, the State of Tennessee comprised most of the northern border of the Confederate States of America in the West. Defending that border was difficult for the Confederacy because Union troops might use any of three major rivers (the Mississippi, which flows south to the Gulf of Mexico, and the Tennessee and Cumberland rivers, which flow north to the Ohio River) to invade the South.
Confederate Forts
In 1861, the State of Tennessee constructed earthen forts on the Tennessee and Cumberland rivers to prevent federal invasions from the north. Slaves and soldiers built Fort Donelson on a hill on the west bank of the Cumberland River near the Tennessee-Kentucky border. The fort had several shore batteries that defenders could use to fire on the river, a system of earthworks encircled it on the landside.
Grant Advances Against Fort Henry
By late 1861, President Abraham Lincoln was pressuring Union commanders in the West to invade the South. On January 30, 1862, the Western Theater commander, General Henry Halleck, reluctantly approved Brigadier General Ulysses S. Grant’s plan to attack Fort Henry, on the Tennessee River, just twelve miles west of Fort Donelson. Eager to move, Grant left Cairo, Illinois on February 2, with 15,000 soldiers, plus a flotilla of seven gunboats commanded by United States Navy Flag Officer Andrew Hull Foote. On February 6, Confederate Brigadier General Lloyd Tilghman surrendered Fort Henry after a seventy-five-minute bombardment by Foote’s gunboats.
Grant Advances Against Fort Donelson
Following the surrender of Fort Henry, Grant turned his attention to Fort Donelson. He marched his army toward the Cumberland River on February 12 and 13. After traversing the twelve-mile span between the two forts, Grant positioned his troops in a semi-circle around the western side of Fort Donelson.
Failed Naval Bombardment
On February 14, Foote’s flotilla traveled up the Cumberland River and attempted to reduce the fort with naval gunfire from the eastern side. The bombardment was ineffective, however, because the Confederates held the higher ground. Eventually, Foote’s gunboats withdrew, setting the stage for a land engagement.
Confederate Defenders
After the fall of Fort Henry, General A. S. Johnston, the Confederate commander in the West, reinforced the garrison at Fort Donelson with 12,000 troops accompanied by generals Gideon J. Pillow, Simon B. Buckner, Sr., and John B. Floyd. Upon his arrival at Fort Donelson, Floyd assumed command of the 17,000-man garrison. Grant’s army had swollen to about 25,000 soldiers when reinforcements sent by Halleck arrived. Seeing that Grant had them surrounded, the Confederate generals attempted a breakout to avoid being trapped.
Failed Confederate Breakout
On the morning of February 15, Confederate troops surged out of the fort, attacking the Union right flank, commanded by Brigadier General John McClernand. The Confederates drove McClernand’s men back, but they did not rout them. By early afternoon, reinforcements from the Union center arrived and stabilized the situation.
Although a breakout was still possible, Pillow ordered his men back to their trenches to resupply before making another attempt. Taking advantage of the delay, Grant ordered a counterattack on the left, forcing the Confederates back into a defensive position. By nightfall, the Federals reclaimed much of the ground they lost in the morning.
Floyd and Buckner Desert
During the night, the Confederate commanders concluded that their situation was hopeless. Fearing harsh reprisals for political acts they committed before the war, Floyd and Pillow turned the command over to Buckner and fled during the night to evade being captured.
Buckner Surrenders
The Federals awoke the next morning, surprised to see white flags of truce flying over Fort Donelson. Buckner requested an armistice and asked Grant for his terms of surrender. Grant replied, “No terms except unconditional and immediate surrender can be accepted.” Buckner had reason to believe that Grant would be more generous because of their personal relationship in the Union Army before the war. When Grant did not yield, Buckner could only capitulate to what he termed Grant’s “ungenerous and unchivalrous terms.”
Outcome of the Battle of Fort Donelson
The Confederates suffered about 14,000 casualties at the Battle of Fort Donelson, compared with Union losses of about 2,500 men. However, the 12,000 prisoners inflated the Confederate losses.
Although the total casualty rate for both sides was small in comparison with later battles in the war, the fall of Fort Donelson was a serious blow to the Confederacy. It forced them to give up activities in Kentucky and move their operations deeper into Tennessee.
The victory also boosted faltering morale in the North. In the battle’s aftermath, “Unconditional Surrender” Grant became an instant celebrity, and army officials promoted him to major general, second-in-command in the West. Coupled with the capture of Fort Henry, the Union controlled two major waterways in the West from which to launch impending invasions of the South.
Timeline
- 1861 — Tennessee constructed earthen forts on the Tennessee and Cumberland rivers to prevent federal invasions from the north.
- Late 1861 — President Abraham Lincoln pressured Union commanders in the West to invade the South.
- 1862, January 30 — Henry Halleck approved Ulysses S. Grant’s plan to attack Fort Henry.
- 1862, February 2 — Grant left Cairo, Illinois, with 15,000 soldiers and seven gunboats commanded by Andrew Hull Foote.
- 1862, February 6 — Union forces won the Battle of Fort Henry.
- 1862, February 12 — Grant marched toward Fort Donelson, and the Battle of Fort Donelson started.
- 1862, February 13 — Grant completed his march from Fort Henry and positioned Union troops around Fort Donelson.
- 1862, February 14 — Foote’s gunboats bombarded Fort Donelson but withdrew after Confederate artillery damaged the fleet.
- 1862, February 15
- Confederate troops attacked the Union right flank and opened a possible escape route.
- Gideon J. Pillow ordered Confederate troops back to their trenches, allowing Grant to launch a counterattack.
- Union forces recovered much of the ground they had lost earlier in the day.
- 1862, February 16
- John B. Floyd and Gideon J. Pillow escaped after transferring command to Simon B. Buckner.
- Buckner accepted Grant’s demand for an immediate and unconditional surrender.
- The Battle of Fort Donelson ended in a Union victory.
AP US History
Definition
Battle of Fort Donelson (1862) — The Battle of Fort Donelson was a major Union victory fought in Tennessee from February 12 to February 16, 1862. General Ulysses S. Grant surrounded the Confederate fort after capturing Fort Henry. A Union naval bombardment failed, but Confederate commanders also failed to complete a breakout on February 15. Generals John B. Floyd and Gideon Pillow escaped, leaving General Simon B. Buckner to accept Grant’s demand for an immediate and unconditional surrender.
Alignment
The Battle of Fort Donelson is part of the following AP US History sections:
