Battle of Fort Donelson The Battle of Fort Donelson was fought from February 11 to February 16 , 1862 , in the Western Theater of the American Civil War . The capture of the fort by Union forces opened the Cumberland River , an important avenue for the invasion of the South . The success elevated Brig . Gen . Ulysses S . Grant from an obscure and largely unproven leader to the rank of major general , earning him the nickname " Unconditional Surrender " Grant in the process ( using his first two initials , " U . S . " ) . The battle followed the capture of Fort Henry on February 6 . Grant moved his army 12 miles overland to Fort Donelson on February 12 and February 13 and conducted several small probing attacks . ( Although the name was not yet in use , the troops serving under Grant were the nucleus of the Union ' s Army of the Tennessee . ) On February 14 , U . S . Navy gunboats under Flag Officer Andrew H . Foote attempted to reduce the fort with naval gunfire , but were forced to withdraw after sustaining heavy damage from Donelson ' s water batteries . On February 15 , with their fort surrounded , the Confederates , commanded by Brig . Gen . John B . Floyd , launched a surprise attack against Grant ' s army , attempting to open an avenue of escape . Grant , who was away from the battlefield at the start of the attack , arrived to rally his men and counterattack . Despite achieving a partial success and opening the way for a retreat , Floyd lost his nerve and ordered his men back to the fort . On the following morning , Floyd and his second - in - command , Brig . Gen . Gideon J . Pillow , panicked and relinquished command to Brig . Gen . Simon Bolivar Buckner ( later Governor of the Commonwealth of Kentucky ) , who agreed to accept the unconditional surrender terms offered by Grant . Background . The battle of Fort Donelson took place shortly after the battle of Fort Henry , Tennessee , February 6 , 1862 , in which Grant and Foote captured the fort and opened the Tennessee River for future Union movements . About 2 , 500 of the Confederate defenders at Fort Henry escaped before the surrender , marching the 12 miles ( 19 km ) east to Fort Donelson . The Confederates faced some difficult choices . Grant ' s army was now between Confederate Gen . Albert Sidney Johnston ' s two main forces ( P . G . T . Beauregard at Columbus , Kentucky , with 12 , 000 men , and William J . Hardee at Bowling Green , Kentucky , with 22 , 000 ) . Fort Henry was a deep salient in the center of the line defending Tennessee , and the railroad south of it had been cut , restricting the lateral mobility needed to rush reinforcements to defend against the larger opposing Union forces . Nearby Fort Donelson had only about 5 , 000 men . Union forces might attack Columbus ; they might attack Fort Donelson and thereby threaten Nashville , or Grant and Maj . Gen . Don Carlos Buell ( in Louisville with 45 , 000 men ) might attack Johnston head - on , Grant following behind Buell . Johnston was apprehensive about the ease with which Union gunboats defeated Fort Henry ( not comprehending that the rising Tennessee River played a crucial role as it inundated the fort ) . He was more concerned about the threat from Buell than he was from Grant , suspecting the river operations might simply be a diversion . Johnston decided upon a course of action that forfeited the initiative across most of his defensive line , tacitly admitting that the Confederate defensive strategy for Tennessee was a sham . On February 7 , at a council of war held in the Covington Hotel in Bowling Green , he decided to abandon Western Kentucky by withdrawing Beauregard from Columbus , evacuate Bowling Green , and move his forces south of the Cumberland River at Nashville . Despite his misgivings about its defensibility , Johnston agreed to advice from Beauregard that he should reinforce Fort Donelson with another 12 , 000 men , knowing that a defeat there would mean the inevitable loss of Middle Tennessee and the vital manufacturing and arsenal city of Nashville . Johnston wanted to give command of Fort Donelson to Beauregard , who had performed ably at Bull Run , but the latter declined because of a throat ailment . Instead , the responsibility went to Brig . Gen . John B . Floyd , who had just arrived following an unsuccessful assignment under Robert E . Lee in western Virginia . Floyd was a wanted man in the North for alleged graft and secessionist activities when he was Secretary of War in the administration of President James Buchanan . His background was political , not military , but he was nevertheless the senior brigadier general on the Cumberland . On the Union side , Maj . Gen . Henry W . Halleck , Grant ' s superior as commander of the Department of the Missouri , was also apprehensive . He had authorized Grant to capture Fort Henry , but now he felt that continuing to Donelson was risky . Despite Grant ' s success to date , Halleck had little confidence in him , considering Grant to be reckless . Halleck attempted to convince his own rival , Don Carlos Buell , to take command of the campaign to get his additional forces engaged . However , despite Johnston ' s high regard for Buell , the Union general was in fact as passive as Grant was aggressive . Grant never suspected his superiors were considering relieving him , but he was well aware that any delay or reversal might be an opportunity for Halleck to lose his nerve and cancel the operation . On February 6 , Grant wired to Halleck , " Fort Henry is ours . . . . I shall take and destroy Fort Donelson on the 8th and return to Fort Henry . " This self - imposed deadline was overly optimistic because of three factors : miserable road conditions on the 12 - mile march to Donelson , the need for troops to carry supplies away from the rising flood waters ( by February 8 , Fort Henry was completely submerged ) , and the damage that had been sustained by Foote ' s Western Flotilla in the artillery duel at Henry . If he had been able to move that quickly , Grant might have taken Fort Donelson on that day . Early in the morning of February 11 , Grant held a council of war in which all of his generals supported his plans for an attack on Donelson , with the exception of Brig . Gen . John A . McClernand , who had some reservations . This council in early 1862 was the last one that Grant held for the remainder of the Civil War . Opposing forces . Union . Grant ' s Union army of the District of Cairo consisted of three divisions , commanded by Brig . Gens . McClernand , C . F . Smith , and Lew Wallace . ( Wallace started as a brigade commander in reserve at Fort Henry , but was summoned to Donelson on February 14 and charged with assembling a new division that included reinforcements arriving by steamship , including Charles Cruft ' s brigade on loan from Don Carlos Buell . ) Supporting the infantry divisions were two regiments of cavalry and eight batteries of artillery , altogether almost 25 , 000 men , although at the start of the battle , only 15 , 000 were available . The Western Flotilla under U . S . Navy Flag Officer Andrew H . Foote consisted of four ironclad gunboats ( flagship USS " St . Louis " , USS " Carondelet " , USS " Louisville " , and USS " Pittsburg " ) and three wooden ( " timberclad " ) gunboats ( USS " Conestoga " , USS " Tyler " , and USS " Lexington " ) . USS " Essex " and had been damaged at Fort Henry and were being repaired . Confederate . Floyd ' s Confederate force of approximately 17 , 000 men consisted of three divisions , garrison troops , and attached cavalry . The three divisions were commanded by Floyd ( replaced by Colonel Gabriel C . Wharton when Floyd took command of the entire force ) and Brig . Gens . Bushrod Johnson and Simon Bolivar Buckner . During the battle , Johnson , the engineering officer who had briefly commanded Fort Donelson in late January , was effectively superseded by Brig . Gen . Gideon J . Pillow ( Grant ' s opponent at his first battle , Belmont ) , who had been displaced from overall command of the fort when the more - senior Floyd arrived . The garrison troops were commanded by Col . John W . Head and the cavalry by Col . Nathan Bedford Forrest . Fort Donelson was named for Brig . Gen . Daniel S . Donelson , who selected its site and began construction in 1861 . It was considerably more formidable than the hapless Fort Henry . It rose about 100 feet ( 30 m ) on dry ground above the Cumberland River , which allowed for plunging fire against attacking gunboats , an advantage Fort Henry did not enjoy . The river batteries included ten 32 - pounder smoothbore cannons , a 6 . 5 - inch rifle , and a 10 - inch Columbiad . There were three miles ( 5 km ) of trenches in a semicircle around the fort and the small town of Dover . The trenches , located on a commanding ridge and fronted by dense abatis , backed up by artillery , were manned by Buckner and his Bowling Green troops on the right ( with his flank anchored on Hickman Creek ) and Johnson / Pillow on the left ( with his flank near the Cumberland River ) . Facing them from left to right were Smith , Lew Wallace ( arrived February 14 ) , and McClernand . McClernand ' s right flank , facing Pillow , had insufficient men to reach overflowing Lick Creek , so was left unanchored . Through the center of the Confederate line ran the marshy Indian Creek and this point was defended primarily by artillery overlooking it on each side . Battle . Preliminary movements and attacks ( February 12 – 13 ) . On February 12 , most of the Union troops departed Fort Henry and proceeded about 5 miles ( 8 km ) on the two main roads leading between the forts . They were delayed most of the day by a cavalry screen commanded by Nathan Bedford Forrest . The USS " Carondelet " was the first gunboat to arrive up the river , and she promptly fired numerous shells into the fort , testing its defenses before retiring . Grant arrived on February 12 and established his headquarters near the left side of the front of the line , at the Widow Crisp ' s house . On February 13 , several smaller probing attacks were carried out against the Confederate defenses , essentially ignoring orders from Grant that no general engagement be provoked . On the Union left , C . F . Smith sent two of his four brigades ( under Cols . Jacob Lauman and John Cook ) to test the defenses along his front . The attack suffered light casualties and made no gains , but Smith was able to keep up a harassing fire throughout the night . On the right , McClernand also ordered an unauthorized attack . Two regiments of Col . William R . Morrison ' s brigade , along with one regiment , the 48th Illinois , from Col . W . H . L . Wallace ' s brigade , were ordered to seize a battery ( " Redan Number 2 " ) that had been plaguing their position . Isham N . Haynie , Colonel of the 48th Illinois , was senior in rank to Colonel Morrison . Although rightfully in command of two of the three regiments , Morrison volunteered to turn over command once the attack was under way . When the attack commenced , Morrison was wounded , eliminating any leadership ambiguity , but for some reason Haynie never fully took control and the attack was repulsed . Some wounded men caught between the lines burned to death in grass fires ignited by the artillery . Although the weather had been mostly only wet up to this point in the campaign , a snow storm arrived the night of February 13 , with strong winds that brought temperatures down to 10 – 12 °F ( - 12 °C ) and deposited 3 inches ( 8 cm ) of snow by morning . Guns and wagons were frozen to the earth . Because of the proximity of the enemy lines and the active sharpshooters , the soldiers could not light campfires for warmth or cooking , and both sides were miserable that night , many having arrived without blankets or overcoats . Reinforcements and naval battle ( February 14 ) . At 1 : 00 a . m . on February 14 , Floyd held a council of war in his headquarters , the Dover Hotel , and there was general agreement that Fort Donelson was probably untenable . General Pillow was designated to lead a breakout attempt . Troops were moved behind the lines and the assault readied , but at the last minute a Union sharpshooter killed one of Pillow ' s aides . Pillow , normally quite aggressive in battle , was unnerved and announced that since their movement had been detected , the breakout had to be postponed . Floyd was furious at this change of plans , but by then it was too late in the day to proceed . Also on February 14 , General Lew Wallace ' s brigade arrived from Fort Henry around noon and Foote ' s flotilla arrived , bringing six gunboats and another 10 , 000 Union reinforcements on twelve transport ships . Wallace assembled these new troops into a third division of two brigades , under Cols . John M . Thayer and Charles Cruft , and occupied the center of the line facing the Confederate trenches . This provided sufficient troops to extend McClernand ' s right flank to be anchored on Lick Creek , by moving Col . John McArthur ' s brigade of Smith ' s division from the reserve to a position from which they intended to plug the 400 - yard gap at first light the next morning . As soon as Foote arrived , Grant urged him to attack the fort ' s river batteries . Despite his reluctance to proceed before adequate reconnaissance , by 3 : 00 p . m . Foote moved his gunboats in close to the shore and opened fire , just as he had done at Fort Henry . Waiting until the gunboats were within 400 yards , the Confederate gunners returned fire . The artillery pummeled the fleet . Foote was wounded ( ironically in his foot ) and the wheelhouse to his flagship , USS " St . Louis " , carried away . Uncontrollable , she floated helplessly downriver . USS " Louisville " was also disabled and " Pittsburg " began to take on water . The damage to the fleet was terrific . From a total of 500 Confederate shots , " St . Louis " was hit 59 times , " Carondelet " 54 , " Louisville " 36 , and " Pittsburg " 20 . Foote had miscalculated following his easy success at Fort Henry . Historian Kendall Gott suggested that it would have been more prudent to stay as far downriver as possible , and use the fleet ' s longer - range guns to reduce the fort . An alternative might have been to run the batteries , probably at night as would be done successfully in the 1863 Vicksburg Campaign ; once past the fixed river batteries , Fort Donelson would have been defenseless . Eight Union sailors were killed and 44 wounded while the Confederates lost none ; Captain Joseph Dixon of the river batteries had been killed the previous day during " Carondelet " < nowiki > ' < / nowiki > s bombardment . However , on land the Confederates were surrounded by well - armed Union soldiers , and while the Union boats had been damaged , they still controlled the Cumberland River . Grant realized that any success at Donelson would have to be carried by the army without strong naval support , and he wired Halleck that he might have to resort to a siege . Breakout attempt ( February 15 ) . Despite their unexpected naval success , the Confederate generals were still gloomy about their chances in the fort and held another late - night council of war , deciding to retry their aborted escape plan . On the morning of February 15 , the Confederates launched a dawn assault by Pillow against McClernand ' s division on the still unprotected right flank of the Union line . The Union troops were not caught entirely by surprise because they had been unable to sleep in the cold weather . But one Union officer was surprised — Ulysses S . Grant . Not expecting any land actions that he did not initiate himself , Grant was up before dawn and traveled to visit Flag Officer Foote down river on his flagship . He left orders that none of his generals was to initiate an engagement , and he left no one designated as second - in - command during his absence . The Confederate plan was for Pillow to push McClernand out of the way and for Buckner to move his division across Wynn ' s Ferry Road and act as rear guard for the remainder of the army as it withdrew from Donelson and moved east . A lone regiment from Buckner ' s division — the 30th Tennessee — was designated to stay in the trenches and prevent Federal pursuit . The attack started well , and after two hours of heavy fighting , Pillow ' s men were able to push McClernand out of the way and open the escape route . It was in this attack that Union troops in the West first heard the famous , unnerving rebel yell . The attack was primarily successful because of the poor positioning of McClernand ' s troops , and a flanking attack by sometimes - dismounted Confederate cavalry under Forrest . The brigades of Cols . Richard Oglesby and John McArthur were hit hardest ; they withdrew in a generally orderly manner to the rear for regrouping and resupply . McClernand sent messengers to obtain assistance from Lew Wallace , but Wallace was reluctant to act without orders from Grant , who was still absent . McClernand ' s withdrawal had not yet assumed the frantic energy of a rout , but ammunition was running out . ( The army of former quartermaster Ulysses S . Grant had not yet learned to organize supply lines effectively , and extra ammunition was not immediately available to these front - line brigades . ) A second messenger arrived at Wallace ' s headquarters in tears , crying " Our right flank is turned ! . . . The whole army is in danger ! " Wallace finally released one of his brigades , under Col . Charles Cruft , to aid McClernand . Cruft ' s brigade replaced Oglesby ' s and McArthur ' s in the line , but as they realized they were being flanked , they too began to fall back . Not everything was going well with the Confederate advance . By 9 : 30 a . m . , as the lead Union brigades were falling back , Nathan Bedford Forrest urged Bushrod Johnson to launch an all - out attack on these disorganized troops . Johnson was too cautious to approve of a general assault , but he did agree to keep the infantry moving slowly forward . Two hours into the battle , Gen . Pillow realized that Buckner ' s wing was not attacking alongside his . After a confrontation between the two generals , Buckner ' s troops moved out and , combined with the right flank of Pillow ' s wing , hit W . H . L . Wallace ' s brigade . But this delay of Buckner ' s provided time for Lew Wallace to reinforce McClernand before he was completely routed . The Confederate offensive stopped around 12 : 30 p . m . , when Col . Thayer ' s Union troops formed a defensive line on a ridge astride Wynn ' s Ferry Road . The Confederates assaulted three times unsuccessfully and withdrew to a ridge one half mile ( 1 km ) back . Nevertheless , they had had a good morning . They had pushed the Union defenders back one to two miles ( 2 – 3 km ) and had opened their escape route . Grant , who apparently could not hear the sound of battle , eventually was notified by an aide . He galloped 7 miles ( 11 km ) over icy roads to reach Wallace ' s headquarters by 1 : 00 p . m . and was dismayed to find the confusion and lack of leadership he had left behind . McClernand grumbled " This army wants a head . " Grant replied , " It seems so . Gentlemen , the position on the right must be retaken . " But true to his nature , Grant did not panic at the Confederate assault . As he rode back from the river , he heard the sounds of guns and sent word back to Foote to start a demonstration of naval gunfire , assuming that his troops would be demoralized and could use the encouragement . Grant observed that some of the Confederates ( Buckner ' s ) were fighting with knapsack s filled with three days of rations , which implied to him that they were attempting to escape , not pressing for a combat victory . He told an aide , " The one who attacks first now will be victorious . The enemy will have to be in a hurry if he gets ahead of me . " Despite seeing that his attack was successful and his escape route was open , by 1 : 30 p . m . Pillow believed he should regroup and resupply his wing before pushing forward and , to the amazement of Floyd and Buckner , he ordered his men back to their trenches . At that moment , Floyd lost his nerve and , believing that C . F . Smith ' s division was being heavily reinforced , ordered the entire force back inside the lines of Fort Donelson . Grant moved quickly to exploit the opening that the indecisive Floyd had left him and told Smith that " All has failed on our right — you must take Fort Donelson . " Smith replied , " I will do it . " Smith formed his two remaining brigades to make an attack . Lauman ' s brigade would be the main attack , spearheaded by Col . James Tuttle ' s 2nd Iowa Infantry . Cook ' s brigade would be in support to the right and rear and act as a feint to draw fire away from Lauman ' s brigade . Smith ' s two - brigade counterattack quickly succeeded in seizing the outer line of entrenchments on the Confederate right , where the 30th Tennessee , commanded by Col . John W . Head , had been left behind from Buckner ' s division . Despite repeated counterattacks over two hours , the Confederates could not repel Smith from the captured earthworks . The Union was now poised to seize both Fort Donelson and its river batteries when light returned the next morning . On the Union right , Lew Wallace formed an attacking column with three brigades — one from his own division , one from McClernand ' s , and one from Smith ' s . Wallace ' s old brigade from Smith ' s Division , now commanded by Col . Morgan L . Smith , was chosen to lead the attack . The brigades of Cruft ( Wallace ' s Division ) and Leonard F . Ross ( McClernand ' s Division ) were placed in support on the flanks . Waiting just a moment for Col . Smith to light a cigar , Wallace ordered the attack forward . Smith ' s brigade advanced a short distance up the hill , repeatedly rushing and then falling to the ground in the prone position , all the while listening to taunts from Drake ' s Confederate brigade opposing them . Wallace ' s troops charged and succeeded in retaking all the ground lost that morning . Smith was on horseback immediately behind his lead regiment and a bullet shot off the cigar close to his mouth , but he coolly replaced it with a fresh one . By nightfall , all of the Confederate troops had been driven back to their original positions . Grant began planning to resume his assault in the morning , although neglecting to close the escape route that Pillow had opened . Surrender ( February 16 ) . Nearly 1 , 000 soldiers on both sides had been killed , with about 3 , 000 wounded still on the field ; some froze to death in the snowstorm , many Union soldiers having thrown away their blankets and coats . Unaccountably , Generals Floyd and Pillow were happy about the day ' s performance and wired General Johnston at Nashville that they had won a great victory . Buckner , however , argued that they were in a desperate position that was getting worse as Union reinforcements were arriving . At their final council of war in the Dover Hotel at 1 : 30 a . m . on February 16 , he stated that if C . F . Smith attacked again , he could only hold for 30 minutes , and he estimated that the cost of defending the fort would be as high as 75 % casualties . Buckner ' s defeatism finally carried the meeting . Any large - scale escape would be difficult , since most of the river transports were currently transporting wounded men to Nashville and would not return in time to evacuate the command . Floyd realized that he was about to be captured and would probably be tried for his alleged previous misconduct by the North . He promptly turned over his command to General Pillow , who also feared Northern reprisals . Pillow passed it in turn to General Buckner , who agreed to remain behind and surrender the army . Pillow escaped by small boat across the Cumberland in the night . Floyd left the next morning on the only steamer available , taking his two regiments of Virginia infantry . Disgusted at the show of cowardice , a furious Nathan Bedford Forrest announced , " I did not come here to surrender my command . " He stormed out of the meeting and led about 700 of his cavalrymen to escape the fort . Forrest ' s horsemen rode toward Nashville through the shallow , icy waters of Lick Creek , encountering no enemy and confirming that many more could have escaped by the same route , if Buckner had not posted guards to prevent any such attempts . On the morning of February 16 , Buckner sent a note to Grant requesting an armistice and asking terms of surrender . The note first reached General Smith . Smith stated " I ' ll make no terms with Rebels with arms in their hands — my terms are unconditional and immediate surrender " . When the note finally reached Grant , Smith again told Grant to offer " no terms to the Rebels " . Buckner had hoped that Grant would offer generous terms because of their long friendship . In fact in 1854 , Grant had been removed from command at an Army post in California , allegedly because of alcoholism . Buckner , a fellow U . S . Army officer , loaned Grant sufficient money for him to return home to Illinois after he had been forced to resign his commission . To his dismay , Grant showed no mercy towards men he considered to be rebelling against the Federal government . His brusque reply became one of the most famous quotes of the war , earning Grant the nickname of " Unconditional Surrender " : Grant was not bluffing . Smith was now in a good position , having captured the outer lines of fortifications , and was under orders to launch an attack , supported by the other divisions , the next day . Grant believed his position allowed him to forego his planned siege and successfully storm the fort . Buckner responded to Grant ' s demand : Grant was courteous to Buckner following the surrender and offered to loan him money to see him through his impending imprisonment , but Buckner declined . The surrender was a humiliation for Buckner personally , but also a strategic defeat for the Confederacy , which lost more than 12 , 000 men , 48 artillery pieces and much equipment , as well as control of the Cumberland River , which led to the evacuation of Nashville . This army was the first of three Confederate armies that Grant would capture during the war . ( The second was John C . Pemberton ' s at the Siege of Vicksburg and the third Robert E . Lee ' s Army of Northern Virginia at Appomattox ) . Buckner also turned over considerable military equipment and provisions , which Grant ' s hungry troops needed badly . More than 7 , 000 Confederate prisoners of war were eventually transported from Fort Donelson to Camp Douglas in Chicago ; others were sent elsewhere throughout the North . Buckner was held as a prisoner at Fort Warren in Boston until he was exchanged that August . Aftermath . The casualties at Fort Donelson were heavy primarily because of the large Confederate surrender . Union losses were 2 , 691 ( 507 killed , 1 , 976 wounded , 208 captured / missing ) , Confederate 13 , 846 ( 327 killed , 1 , 127 wounded , 12 , 392 captured / missing ) . Cannons were fired and church bells rung throughout the North at the news . The Chicago " Tribune " wrote that " Chicago reeled mad with joy . " The capture of Forts Henry and Donelson were the first significant Union victories in the war and opened two great rivers as avenues of invasion to the heartland of the South . Grant was promoted to major general of volunteers , second in seniority only to Henry W . Halleck in the West . After newspapers reported that he had won the battle with a cigar clamped in his teeth , he was inundated with cigars sent to him by many admirers . ( He would eventually die of throat cancer , likely brought on by his heavy smoking ) . Close to a third of all Albert Sidney Johnston ' s forces were prisoners ; Grant had captured more soldiers than all previous American generals combined . Johnston was thereby deprived of over twelve thousand soldiers who would otherwise have provided a decisive advantage at the impending Battle of Shiloh in less than two months time . The rest of Johnston ' s forces were 200 miles ( 320 km ) apart between Nashville and Columbus with Grant ' s army between them , now controlling all the rivers and railroads . General Buell ' s army was threatening Nashville , while John Pope was threatening Columbus . Johnston evacuated Nashville on February 23 , surrendering this important industrial center to the Union ; it was the first Confederate state capital to fall . Columbus was evacuated on March 2 . Most of Tennessee fell under Union control , as did all of Kentucky , although both were subject to periodic Confederate raiding . The site of the battle has been preserved by the National Park Service as Fort Donelson National Battlefield .