Siege of Vicksburg The Siege of Vicksburg ( May 18 – July 4 , 1863 ) was the final major military action in the Vicksburg Campaign of the American Civil War . In a series of maneuvers , Union Maj . Gen . Ulysses S . Grant and his Army of the Tennessee crossed the Mississippi River and drove the Confederate Army of Vicksburg led by Lt . Gen . John C . Pemberton into the defensive lines surrounding the fortress city of Vicksburg , Mississippi . When two major assaults ( May 19 and May 22 , 1863 ) against the Confederate fortifications were repulsed with heavy casualties , Grant decided to besiege the city beginning on May 25 . With no reinforcement , supplies nearly gone , and after holding out for more than forty days , the garrison finally surrendered on July 4 . This action ( combined with the surrender of Port Hudson to Maj . Gen . Nathaniel P . Banks on July 9 ) yielded command of the Mississippi River to the Union forces , who would hold it for the rest of the conflict . The Confederate surrender following the siege at Vicksburg is sometimes considered , when combined with Gen . Robert E . Lee ' s defeat at Gettysburg by Maj . Gen . George G . Meade the previous day , the turning point of the war . It also cut off communication with Confederate forces in the Trans - Mississippi Department for the remainder of the war . Background . After crossing the Mississippi River south of Vicksburg at Bruinsburg and driving northeast , Grant won battles at Port Gibson and Raymond and captured Jackson , the Mississippi state capital on May 14 , 1863 , forcing Pemberton to withdraw westward . Attempts to stop the Union advance at Champion Hill and Big Black River Bridge were unsuccessful . Pemberton knew that the corps under Maj . Gen . William T . Sherman was preparing to flank him from the north ; he had no choice but to withdraw or be outflanked . Pemberton burned the bridges over the Big Black River and took everything edible in his path , both animal and plant , as he retreated to the well - fortified city of Vicksburg . The Confederates evacuated Hayne ' s Bluff , which was occupied by Sherman ' s cavalry on May 19 , and Union steamboats no longer had to run the guns of Vicksburg , now being able to dock by the dozens up the Yazoo River . Grant could now receive supplies more directly than by the previous route , which ran through Louisiana , over the river crossing at Grand Gulf and Bruinsburg , then back up north . Over three quarters of Pemberton ' s army had been lost in the two preceding battles and many in Vicksburg expected General Joseph E . Johnston , in command of the Confederate Department of the West , to relieve the city — which he never did . Large masses of Union troops were on the march to invest the city , repairing the burnt bridges over the Big Black River ; which Grant ' s forces crossed on May 18 . Johnston sent a note to his general , Pemberton , asking him to sacrifice the city and save his troops , something Pemberton would not do . ( Pemberton , a Northerner by birth , was probably influenced by his fear of public condemnation if he abandoned Vicksburg . ) Opposing forces and the defenses of Vicksburg . As the Union forces approached Vicksburg , Pemberton could put only 18 , 500 troops in his lines . Grant had over 35 , 000 , with more on the way . However , Pemberton had the advantage of terrain and fortifications that made his defense nearly impregnable . The defensive line around Vicksburg ran approximately 6 . 5 miles , based on terrain of varying elevations that included hills and knobs with steep angles for an attacker to ascend under fire . The perimeter included many gun pits , forts , trenches , redoubt s , and lunettes . The major fortifications of the line included Fort Hill , on a high bluff north of the city ; the Stockade Redan , dominating the approach to the city on Graveyard Road from the northeast ; the 3rd Louisiana Redan ; the Great Redoubt ; the Railroad Redoubt , protecting the gap for the railroad line entering the city ; the Square Fort ( Fort Garrott ) ; a salient along the Hall ' s Ferry Road ; and the South Fort . Maj . Gen . Ulysses S . Grant ' s Union Army of the Tennessee brought three corps to the battle : the XIII Corps , under Maj . Gen . John A . McClernand ; the XV Corps , under Maj . Gen . William T . Sherman ; and the XVII Corps , under Maj . Gen . James B . McPherson . Lt . Gen . John C . Pemberton ' s Confederate Army of Mississippi inside the Vicksburg line consisted of four divisions , under Maj . Gens . Carter L . Stevenson , John H . Forney , Martin L . Smith , and John S . Bowen . Assaults . Grant wanted to overwhelm the Confederates before they could fully organize their defenses and ordered an immediate assault against Stockade Redan for May 19 . Troops from Sherman ' s corps had a difficult time approaching the position under rifle and artillery fire from the 36th Mississippi Infantry , Brig . Gen . Louis Hébert ' s brigade — they had to negotiate a super extremely really not kiddingly steep ravine protected by superman and cross a , ditch before attacking the walls of the redan . This first attempt was easily repulsed . Grant ordered an artillery bombardment to soften the defenses and at about 2 p . m . , Sherman ' s division under Maj . Gen . Francis P . Blair tried again , but only a small number of men were able to advance even as far as the ditch below the redan . The assault collapsed in a melee of rifle fire and hand grenades lobbing back and forth . The failed Federal assaults of May 19 damaged Union morale , deflating the confidence the soldiers felt after their string of victories across Mississippi . They were also costly , with casualties of 157 killed , 777 wounded , and 8 missing , versus Confederate casualties of 8 killed and 62 wounded . The Confederates , assumed to be demoralized , had regained their fighting edge . Grant planned another assault for May 22 , but this time with greater care ; they would first reconnoiter thoroughly and soften up the defenses with artillery and naval gunfire . The lead units were supplied with ladders to ascend the fortification walls . Grant did not want a long siege , and this attack was to be by the entire army across a wide front . Despite their bloody repulse on May 19 , Union troops were in high spirits , now well - fed with provisions they had foraged . On seeing Grant pass by , a soldier commented , " Hardtack " . Soon all Union troops in the vicinity were yelling , " Hardtack ! Hardtack ! " The Union served hardtack , beans , and coffee the night of May 21 . Everyone expected that Vicksburg would fall the next day . Union forces bombarded the city all night , from 220 artillery pieces and naval gunfire from Rear Adm . David D . Porter ' s fleet in the river , and while causing little property damage , they damaged Confederate civilian morale . On the morning of May 22 , the defenders were bombarded again for four hours before the Union attacked once more along a three - mile front at 10 a . m . Sherman attacked once again down the Graveyard Road , with 150 volunteers ( nicknamed the Forlorn Hope detachment ) leading the way with ladders and planks , followed by the divisions of Blair and Brig . Gen . James M . Tuttle , arranged in a long column of regiments , hoping to achieve a breakthrough by concentrating their mass on a narrow front . They were driven back in the face of heavy rifle fire . Blair ' s brigades under Cols . Giles A . Smith and T . Kilby Smith made it as far as a ridge 100 yards from Green ' s Redan , the southern edge of the Stockade Redan , from where they poured heavy fire into the Confederate position , but to no avail . Tuttle ' s division , waiting its turn to advance , did not have an opportunity to move forward . On Sherman ' s far right , the division of Brig . Gen . Frederick Steele spent the morning attempting to get into position through a ravine of the Mint Spring Bayou . McPherson ' s corps was assigned to attack the center along the Jackson Road . On their right flank , the brigade of Brig . Gen . Thomas E . G . Ransom advanced to within 100 yards of the Confederate line , but halted to avoid dangerous flanking fire from Green ' s Redan . On McPherson ' s left flank , the division of Maj . Gen . John A . Logan was assigned to assault the 3rd Louisiana Redan and the Great Redoubt . The brigade of Brig . Gen . John E . Smith made it as far as the slope of the redan , but huddled there , dodging grenades until dark before they were recalled . Brig . Gen . John D . Stevenson ' s brigade advanced well in two columns against the redoubt , but their attack also failed when they found their ladders were too short to scale the fortification . Brig . Gen . Isaac F . Quinby ' s division advanced a few hundred yards , but halted for hours while its generals engaged in confused discussions . On the Union left , McClernand ' s corps moved along the Baldwin Ferry Road and astride the Southern Railroad of Mississippi . The division of Brig . Gen . Eugene A . Carr was assigned to capture the Railroad Redoubt and the 2nd Texas Lunette ; the division of Brig . Gen . Peter J . Osterhaus was assigned the Square Fort . Carr ' s men achieved a small breakthrough at the 2nd Texas Lunette and requested reinforcements . By 11 a . m . , it was clear that a breakthrough was not forthcoming and the advances by Sherman and McPherson were failures . Just then , Grant received a message from McClernand , which stated that he was heavily engaged , the Confederates were being reinforced , and he requested a diversion on his right from McPherson ' s corps . Grant initially refused the request , telling McClernand to use his own reserve forces for assistance ; Grant was mistakenly under the impression that McClernand had been lightly engaged and McPherson heavily , although the reverse was true . McClernand followed up with a message that was partially misleading , implying that he had captured two forts — " The Stars and Stripes are flying over them . " — and that another push along the line would achieve victory for the Union Army . Although Grant once again demurred , he showed the dispatch to Sherman , who ordered his own corps to advance again . Grant , reconsidering , then ordered McPherson to send Quinby ' s division to aid McClernand . Sherman ordered two more assaults . At 2 : 15 p . m . , Giles Smith and Ransom moved out and were repulsed immediately . At 3 p . m . , Tuttle ' s division suffered so many casualties in their aborted advance that Sherman told Tuttle , " This is murder ; order those troops back . " By this time , Steele ' s division had finally maneuvered into position on Sherman ' s right , and at 4 p . m . , Steele gave the order to charge against the 26th Louisiana Redoubt . They had no more success than any of Sherman ' s other assaults . In McPherson ' s sector , Logan ' s division made another thrust down the Jackson Road at about 2 p . m . , but met with heavy losses and the attack was called off . McClernand attacked again , reinforced by Quinby ' s division , but with no success . Union casualties were 502 killed , 2 , 550 wounded , and 147 missing , about evenly divided across the three corps . Confederate casualties were not reported directly , but are estimated to be under 500 . Grant blamed McClernand ' s misleading dispatches for part of the poor results of the day , storing up another grievance against the political general who had caused him so many aggravations during the campaign . Siege . Historian Shelby Foote wrote that Grant " did not regret having made the assaults ; he only regretted that they had failed . " Grant reluctantly settled into a siege . On May 25 , Lt . Col . John A . Rawlins issued Special Orders No . 140 for Grant : " Corps Commanders will immediately commence the work of reducing the enemy by regular approaches . It is desirable that no more loss of life shall be sustained in the reduction of Vicksburg , and the capture of the Garrison . Every advantage will be taken of the natural inequalities of the ground to gain positions from which to start mines , trenches , or advance batteries . . . . " Grant wrote in his memoirs , " I now determined upon a regular siege — to ' out - camp the enemy , ' as it were , and to incur no more losses . " Federal troops began to dig in , constructing elaborate entrenchments ( the soldiers of the time referred to them as " ditches " ) that surrounded the city and moved closer and closer to the Confederate fortifications . With their backs against the Mississippi and Union gunboats firing from the river , Confederate soldiers and citizens alike were trapped . Pemberton was determined to hold his few miles of the Mississippi as long as possible , hoping for relief from Johnston or elsewhere . A new problem confronted the Confederates . The dead and wounded of Grant ' s army lay in the heat of Mississippi summer , the odor of the deceased men and horses fouling the air , the wounded crying for medical help and water . Grant first refused a request of truce , thinking it a show of weakness . Finally he relented , and the Confederates held their fire while the Union recovered the wounded and dead , soldiers from both sides mingling and trading as if no hostilities existed for the moment . After this truce , Grant ' s army began to fill the 12 - mile ring around Vicksburg . In short time it became clear that even 50 , 000 Union soldiers would not be able to effect a complete encirclement of the Confederate defenses . Pemberton ' s outlook on escape was pessimistic , but there were still roads leading south out of Vicksburg unguarded by Federal troops . Grant found help from Maj . Gen . Henry W . Halleck , the Union general - in - chief . Halleck quickly began to shift Union troops in the West to meet Grant ' s needs . The first of these reinforcements to arrive along the siege lines was a 5 , 000 man division from the Department of the Missouri under Maj . Gen . Francis J . Herron on June 11 . Herron ' s troops , remnants of the Army of the Frontier , were attached to McPherson ' s corps and took up position on the far south . Next came a three division detachment from the XVI Corps led by Brig . Gen . Cadwallader C . Washburn on June 12 , assembled from troops at nearby posts of Corinth , Memphis , and LaGrange . The final significant group of reinforcements to join was the 8 , 000 man strong IX Corps from the Department of the Ohio , led by Maj . Gen . John G . Parke , arriving on June 14 . With the arrival of Parke , Grant had 77 , 000 men around Vicksburg . In an effort to cut Grant ' s supply line , Confederates in Louisiana under Maj . Gen . John G . Walker attacked Milliken ' s Bend up the Mississippi on June 7 . This was mainly defended by untrained colored troops , who fought bravely with inferior weaponry and finally fought off the rebels with help from gunboats , although at horrible cost ; the defenders lost 652 to the Confederate 185 . The loss at Milliken ' s Bend left the Confederates with no hope for relief but from the cautious Johnston . Pemberton was boxed in with lots of inedible munitions and little food . The poor diet was showing on the Confederate soldiers . By the end of June , half were out sick or hospitalized . Scurvy , malaria , dysentery , diarrhea , and other diseases cut their ranks . At least one city resident had to stay up at night to keep starving soldiers out of his vegetable garden . The constant shelling did not bother him as much as the loss of his food . As the siege wore on , fewer and fewer horses , mules , and dogs were seen wandering about Vicksburg . Shoe leather became a last resort of sustenance for many adults . During the siege , Union gunboats lobbed over 22 , 000 shells into the town and army artillery fire was even heavier . As the barrages continued , suitable housing in Vicksburg was reduced to a minimum . A ridge , located between the main town and the rebel defense line , provided a diverse citizenry with lodging for the duration . Over 500 caves were dug into the yellow clay hills of Vicksburg . Whether houses were structurally sound or not , it was deemed safer to occupy these dugouts . People did their best to make them comfortable , with rugs , furniture , and pictures . They tried to time their movements and foraging with the rhythm of the cannonade , sometimes unsuccessfully . Because of these dugouts or caves , the Union soldiers gave the town the nickname of " Prairie Dog Village . " Despite the ferocity of the Union fire against the town , fewer than a dozen civilians were known to have been killed during the entire siege . Command changes . One of Grant ' s actions during the siege was to settle a lingering rivalry . On May 30 , General McClernand wrote a self - adulatory note to his troops , claiming much of the credit for the soon - to - be victory . Grant had been waiting six months for him to slip , ever since they clashed early in the campaign , around the Battle of Arkansas Post . He had received permission to relieve McClernand in January 1863 but waited for an unequivocal provocation . Grant finally relieved McClernand on June 18 . He so diligently prepared his action that McClernand was left without recourse . McClernand ' s XIII Corps was turned over to Maj . Gen . Edward Ord , recovered from a wound sustained at Hatchie ' s Bridge . In May 1864 , McClernand was restored to a command in remote Texas . Another command change occurred on June 22 . In addition to Pemberton at his front , Grant had to be concerned with Confederate forces in his rear under the command of Joseph E . Johnston . He stationed one division in the vicinity of the Big Black River bridge and another reconnoitered as far north as Mechanicsburg , both to act as a covering force . By June 10 , the IX Corps , under Maj . Gen . John G . Parke , was transferred to Grant ' s command . This corps became the nucleus of a special task force whose mission was to prevent Johnston , gathering his forces at Canton , from interfering with the siege . Sherman was given command of this task force and Brig . Gen . Frederick Steele replaced him at the XV Corps . Johnston eventually began moving to relieve Pemberton and reached the Big Black River on July 1 , but he delayed a potentially difficult encounter with Sherman until it was too late for the Vicksburg garrison , and then fell back to Jackson . Sherman would eventually pursue Johnston and capture Jackson on July 17 . Louisiana operations . Throughout the siege Union and Confederate forces kept busy in a supporting role on the Louisiana side of the Mississippi River . Lt . Gen . Edmund Kirby Smith , commander of the Trans - Mississippi Department , received a telegraph from Pemberton on May 9 requesting a movement against Grant ' s communication lines along the Mississippi River . Grant had established important supply depots at Milliken ' s Bend , Young ' s Point , and Lake Providence within Smith ' s jurisdiction , but Smith failed to recognize the importance of Pemberton ' s situation . It was not until June when Smith finally decided to take action on Pemberton ' s request , directing Maj . Gen . Richard Taylor to " do something " in favor of the Vicksburg garrison . Taylor commanded the District of Western Louisiana and developed a three - pronged campaign against Grant ' s three supply depots . All three of Taylor ' s assaults were defeated ( see Battle of Milliken ' s Bend , Battle of Young ' s Point and Battle of Lake Providence ) . In response to the growing Confederate activity in the area , Grant decided to dispatch troops from the Vicksburg trenches across the river . The presence of Maj . Gen . John G . Walker ' s Confederate division on the Louisiana side was of particular concern ; its presence could possibly aid a Confederate escape from Vicksburg . Therefore , Brig . Gen . Alfred W . Ellet ' s Mississippi Marine Brigade and Joseph A . Mower ' s brigade from Sherman ' s corps were ordered to the vicinity of Milliken ' s Bend . Mower and Ellet were to cooperate against Walker ' s division , which was stationed in the vicinity of Richmond , Louisiana . Richmond also happened to be an important supply line providing Vicksburg with food from Louisiana . On June 15 , Ellet and Mower defeated Walker and destroyed Richmond , Louisiana . Ellet ' s men returned to De Soto Point and constructed an artillery battery targeting an iron foundry recasting spent Union artillery shells . Construction was begun on June 19 , which placed a 10 - pounder Parrott rifle in a casemate of railroad iron . The targeted foundry was destroyed on June 25 and the next day a second Parrott gun was added to the battery , which continued to harass the defenders until the garrison ' s surrender . Additional Confederate activity in Louisiana occurred on June 29 at Goodrich ' s Landing . Confederates attacked a plantation and army training center run by former slaves . The Confederates destroyed the plantations and captured over a hundred former slaves before disengaging in the face of Ellet ' s Marines . Confederate raids such as these were disruptive and caused damage , but they were only minor setbacks and showed the Confederates could cause only momentary disturbances in the area . Crater at the 3rd Louisiana Redan . Late in the siege , Union troops tunneled under the 3rd Louisiana Redan and packed the mine with 2 , 200 pounds of gunpowder . The explosion blew apart the Confederate lines on June 25 , while an infantry attack made by troops from Logan ' s XVII Corps division , followed the blast . The 45th Illinois Regiment ( known as the " Lead Mine Regiment " ) , under Col . Jasper A . Maltby , charged into the diameter , deep crater with ease , but were stopped by recovering Confederate infantry . The Union soldiers became pinned down while the defenders also rolled artillery shells with short fuses into the pit with deadly results . Union engineers worked to set up a casemate in the crater in order to extricate the infantry , and soon the soldiers fell back to a new defensive line . From the crater left by the explosion on June 25 , Union miners worked to dig a new mine to the south . On July 1 , this mine was detonated but no infantry attack followed . Pioneers worked throughout July 2 and July 3 to widen the initial crater large enough for an infantry column of four to pass through for future anticipated assaults . However , events the following day negated the need for any further assaults . Surrender and aftermath . On July 3 , Pemberton sent a note to Grant , who , as at Fort Donelson , first demanded unconditional surrender . But Grant reconsidered , not wanting to feed 30 , 000 hungry Confederates in Union prison camps , and offered to parole all prisoners . Considering their destitute state , dejected and starving , he never expected them to fight again ; he hoped they would carry home the stigma of defeat to the rest of the Confederacy . In any event , it would have occupied his army and taken months to ship that many troops north . Most of the men who were paroled on July 6 were exchanged and received back into the Confederate Army on August 4 , 1863 , at Mobile Harbor , Alabama . They were back in Chattanooga , Tennessee , by September and some fought in the Battles for Chattanooga in November and against Sherman ' s invasion of Georgia in May 1864 . The Confederate government protested the validity of the paroles on technical grounds and the issue was referred to Grant who , in April 1864 , was general in chief of the Army . The dispute effectively ended all further prisoner exchange s during the war except for hardship cases . Surrender was formalized by an old oak tree , " made historical by the event . " In his " Personal Memoirs , " Grant described the fate of this luckless tree : The surrender was finalized on July 4 , Independence Day , a day Pemberton had hoped would bring more sympathetic terms from the United States . Although the Vicksburg Campaign continued with some minor actions , the fortress city had fallen and , with the surrender of Port Hudson on July 9 , the Mississippi River was firmly in Union hands and the Confederacy split in two . President Lincoln famously announced , " The Father of Waters again goes unvexed to the sea . " Union casualties for the battle and siege of Vicksburg were 4 , 835 ; Confederate were 32 , 697 ( 29 , 495 surrendered ) . The full campaign , since March 29 , claimed 10 , 142 Union and 9 , 091 Confederate killed and wounded . In addition to his surrendered men , Pemberton turned over to Grant 172 cannons and 50 , 000 rifles . Confederate officer Benjamin Morgan Harrod , a Harvard - trained civil engineer who later designed the water and sewage systems for New Orleans , was among the southerners captured at Vicksburg . He was later paroled and joined the engineering division at Petersburg , Virginia . Legacy . Tradition allegedly holds that the Fourth of July ( Independence Day ) holiday was not celebrated by Vicksburg until World War II . This claim has been challenged and large Independence Day celebrations were being held as early as 1907 . The works around Vicksburg are now maintained by the National Park Service as part of Vicksburg National Military Park .