Take Nothing for Granted
May 1863: Vicksburg Campaign
William Terdoslavich
War is fought by rules that all generals can understand. To defend, fortify. To advance, build up supplies, then march. If the enemy gets between you and your supplies, fall back. Then try again.
Major General Ulysses S. Grant played by those rules at Vicksburg and for a while gained nothing. His opponent, Lieutenant General John C. Pemberton, did the same and successfully defended his fortress on the Mississippi. Holding Vicksburg maintained the last link to Arkansas and Texas, vital sources for beef and supplies for the Confederacy. At the same time, the fortress cut the Mississippi in two, denying full use of the river to the Union from end to end.
Grant’s capture of Vicksburg was more than just a siege. It marked a very serious change in Grant’s thinking, the point where he discarded the rulebook and produced the turning point of the war.
So how did Grant pull it off? And how did Pemberton fail?
The Textbook Approach
Terrain did much to strengthen Vicksburg, long before any Confederate fortifications appeared. Its bluffs overlooking the east bank of the Mississippi marked the highest ground between Memphis and Baton Rouge. The town had few roads leading to it, usually perched on high ridges overlooking waterlogged lowlands that made it difficult for troops to march cross-country.
The orthodox approach to taking Vicksburg was an overland advance from a supply base. That is what Grant did in December 1862, moving his army south from Memphis, then building a supply base at Holly Springs, Mississippi, to support the next push. But that plan went up in smoke when General Earl Van Dorn led a cavalry raid against the base, burning the supplies. It was one of the few instances in the Civil War when a cavalry raid worked. Grant pulled his forces back to Memphis, scrounging supplies from surrounding towns and farms. (He admitted in his memoirs that this technique would be useful later, but at present it was only a means to an end.)
Concurrently, Major General William T. Sherman led a corps-sized attack against the bluffs north of Vicksburg, hoping to take the heights by frontal assault. It was a very conventional attack that failed. Grant was forced by circumstances in January 1863 to take the situation in hand when a political appointee, Major General John McClernand, took command of Sherman’s corps and combined it with his own.
As a department commander, Grant outranked McClernand, so he took command of the latter’s combined force and shipped this army to the west bank of the Mississippi, opposite Vicksburg. He now depended on the navy to deliver supplies, making his logistics impervious to Confederate cavalry raids. But Grant still had to find a way to take Vicksburg after failing twice.
Further downriver, a smaller force under Nathaniel Banks was maneuvering its way north from New Orleans to take the smaller fortress at Port Hudson, Louisiana. Banks made constant demands for more troops, which Grant always found a way not to provide because the army was “too busy.”
Grant wasn’t kidding. If he could not go to Vicksburg, he would try going around it. Army-navy cooperation was excellent, so Grant asked Admiral David Dixon Porter to use his flotilla of ironclads to probe the waterways north of Vicksburg, looking for an opportunity to outflank it. Porter tried more than once, but the efforts proved fruitless. Digging a canal through a peninsula across the river from Vicksburg failed. One scheme called for excavating shorter canals to link a myriad of lakes and bayous that peppered the Mississippi’s west bank, hoping that such an improvised route would bypass Vicksburg. But in the end that plan was abandoned due to low water, numerous complications, and insufficient time.
Now it was April. Grant pursued every logical approach, by the book. Nothing worked. A lesser mind would have written off Vicksburg as impossible to take. Blessed with a lesser mind, Pemberton was banking on that conclusion to be his solution.
The answer was to break the rules. Grant now planned to march his army down the west bank of the Mississippi to a point south of Vicksburg. Admiral Porter would run his flotilla of ironclads and steamboats past the Confederate guns, ready to ferry Grant’s men across. For Porter, there would be no return upriver. The Mississippi’s six-knot current would slow down the ironclads, making them lingering targets for Confederate artillerists. Once on the east bank, Grant’s army would be free to maneuver against Pemberton and Vicksburg.
Where Is Grant Going?
Pemberton’s command in Mississippi was caught between two stools. He reported directly to President Jefferson Davis, who told Pemberton never to give up Vicksburg. The Confederacy was depending on Texas and Arkansas for a significant portion of its beef, grain, and manpower to fight the war. Vicksburg was the vital link.
But Pemberton had to obey orders from the theater commander, General Joseph Johnston, whose responsibility ran from the Appalachian Mountains to the Mississippi River. Johnston was more than willing to give up Vicksburg if he could combine Pemberton’s army with other forces to defeat Grant in open battle, provided it was in the right place and at the right time. (Johnston usually could never find the right place at the right time to fight anyone.)
At first, Pemberton handled his problems successfully, by the book. Sending Van Dorn forth to raid Holly Springs forced Grant back. Defending the bluffs north of Vicksburg checked Sherman. Vicksburg itself was well fortified, so attacking it from any point of the compass would not be easy for the Union.
But what was Grant up to? The naval probes into the Yazoo River and Steele’s Bayou were checked by a few brigades and some well-placed artillery holding a few patches of dry ground. As for all that digging on the west bank, what was all that about? Pemberton hunkered down, ready to defend against the next conventional attack. Only conventional attacks were possible, so Pemberton thought.
Then the Union Navy ran past the guns at Vicksburg on the night of April 29. Sure, the guns scored hits, but only one steamer was destroyed. The rest of the flotilla got through. Grant had marched his army down the west bank to Hard Times, Louisiana, ready to cross over to the east bank.
While Grant was making his big move, he befuddled his opponent with two smaller actions. First was massing Sherman’s corps against the bluffs north of Vicksburg, again. Pemberton kept his forces ready to repel the attack that never came. (It was this or let Sherman walk in.)
Then came the Union cavalry raid, led by Colonel Benjamin Grierson. Starting in mid-April, Grierson’s brigade spent the next two weeks knifing its way from Tennessee south through Mississippi into Louisiana. Pemberton had no cavalry handy to stop it. Grierson’s raid didn’t wreck anything irreplaceable. But it distracted Pemberton, who dispatched a few infantry brigades hither and yon to protect a few rail junctions, hoping Grierson would cross paths with one of these “mobile garrisons.” Grierson never did.
Crossing the River
Grant wanted to cross his army from Hard Times to Grand Gulf, but the Confederates were too strong there. Pemberton figured out this was the objective and dispatched 5,000 men to reinforce Brigadier General John Bowen, who commanded another 4,000 men in that area. After getting information from a local escaped slave about a steamboat landing farther south at Bruinsburg, Mississippi, Grant made that his crossing point. That put his army forty miles south of Vicksburg. After landing, McClernand’s corps marched to Port Gibson, some ten miles inland, to face down Bowen’s force, which covered the back way to Grand Gulf.
Pemberton could not move his entire army to Port Gibson to stop Grant. The forty-mile road back to Vicksburg could supply no more than one division. Bowen did his best to hold off McClernand’s corps, but the battle on May 1 only delayed the inevitable. Bowen retreated once he saw the blue hordes outflanking his thin gray line. Grant pushed his troops, but could not trap Bowen, who evacuated the garrison from Grand Gulf.
Pemberton began calling in his scattered forces from all over Mississippi. Grant paused, preparing to detach McClernand’s corps to work with Banks to take Port Hudson. But Banks was away, undertaking a fruitless foray up the Red River into Arkansas. Grant could not afford to wait for Banks to return. Action was needed now. So Grant broke another rule: get rid of his supply line and have his army live off the land, free to move anywhere except back the way he came.
Grant resumed his campaign. By May 7, Sherman’s corps had marched down the west bank of the Mississippi and crossed over to Grand Gulf. The two corps belonging to McClernand and James B. McPherson were operating twelve to eighteen miles to the northeast.
Pemberton figured Grant would now turn northwest, cross the Big Black River, and strike Vicksburg from the south. He dispatched the divisions of William Loring and Carter Stevenson to block such a move. Pemberton wanted to advance his army southeast from Vicksburg to cut Grant’s supply line. (He’s supposed to have one, right?) None existed, but Pemberton didn’t know that. Pemberton was playing the game by the rules. Grant wasn’t.
Pemberton, with 32,000 men under his command, also expected Johnston to show up with 6,000 additional troops at Jackson, the capital of Mississippi. The opportunity existed for the two generals to combine their forces against Grant’s 44,000—not quite even odds, but good enough.
Grant had to keep the linkup from happening. So he did what Pemberton did not expect—he marched northeast to Jackson. McPherson’s corps got there on May 13. Discretion being the better part of valor, Johnston withdrew in the face of a larger force. With Jackson in pocket, Grant pushed McClernand’s corps west toward Vicksburg while using his other two corps to trash the rail line from Jackson westward. This cut any hope of resupplying or reinforcing Pemberton, who now shifted his army to the east to block Grant.
What to Do?
Pemberton was ordered by Jefferson Davis to defend Vicksburg.
Johnston issued orders to Pemberton on May 14 to abandon Vicksburg and join forces.
Pemberton had to make a decision.
In a “council of war,” many of Pemberton’s generals wanted to link up with Johnston, but a few wanted to fight Grant and hang on to Vicksburg. Pemberton took the advice of the few. He advanced eastward down the Vicksburg–Jackson rail line, blundering into Grant’s picket line at Champion Hill on May 15.
The battle pitted three Confederate divisions against six divisions under Grant, with Pemberton enjoying the advantage of high ground. Stevenson’s division held Champion Hill while Loring’s and Stevenson’s divisions were posted on a ridge running south.
McClernand’s corps attacked, with one division taking part of Stevenson’s line and the other two mounting halfhearted pinning attacks against Pemberton’s two divisions. McClernand sent a messenger back to Grant, asking for instructions. The reply was simple: attack. Grant rushed McPherson’s corps to reinforce.
But McClernand was not a fighter. Noting the diffident pinning attacks, Pemberton yanked out his two divisions and sent them to his left to reinforce Stevenson. Grant made a mistake, pulling a division from his far right to hold the line against Pemberton’s reinforced attack. This threw away any chance of cutting Pemberton off from his line of retreat. By 4 P.M., Pemberton saw he could not win the fight against increasing Yankee forces, so he withdrew his force, leaving a single division as a rear guard. Pemberton lost close to 4,000 men out of his force of 21,000. Grant suffered the loss of almost 2,500 out of 29,000.
Retreating to the Big Black River, Pemberton posted 5,000 men to guard the crossing while the rest of his force retreated to Vicksburg. But the defensive position was turned when a Union brigade attacked on its own initiative. This forced out the Confederate rear guard, but also spoiled a chance for Sherman’s corps to cross the river farther north and score another outflank.
Pemberton finally got his force back to Vicksburg. Grant reached the town on May 18, getting word back to Washington of recent developments and calling for reinforcements. Trying to capture the town on the cheap the next day, Grant tried to rush the defenses. McClernand claimed to have taken a stretch of the Confederate line, and Grant maintained his attacks to pin Pemberton’s forces elsewhere so McClernand could exploit the foothold. But McClernand’s report proved false, so men died for nothing. Grant built his siege lines, truly cutting off Vicksburg. He deployed incoming reinforcements to screen all avenues of approach to the north and east, thus keeping Johnston away. (McClernand was eventually relieved by Grant for speaking out of turn to the press, claiming credit for more than he actually did.)
By July 4, southern troops and townspeople were starving. No relief could be expected for Vicksburg. Pemberton acceded to Grant’s demand for an unconditional surrender.
The Score
Grant read the situation shrewdly, paroling the defeated Confederates, knowing they would “quit the war” and go home. Banks returned from his idiot errand to Arkansas and took the surrender of Port Hudson later in July.
The blood price was cheap. From May 1 to July 4, Grant lost about 9,300 men. Pemberton surrendered with 29,500—a total loss for the Confederacy. The Union now had undisputed control of the Mississippi. Grain from the inland states could flow again to New Orleans for export. The South lost all supplies coming from its western states. Grant’s victory also coincided with Meade’s win at Gettysburg. That battle was certainly the dramatic climax of the war, but the true strategic turning point was Vicksburg.
Grant came out of the campaign a changed general. Conventional thinking was a straitjacket he discarded in favor of fierce, ruthless common sense. As he later wrote: “I don’t underrate the value of military knowledge, but if men make war in slavish obedience to the rules, they will fail. No rules can apply to conditions of war as different as those which exist in Europe and America. Consequently, while our generals were working out problems in an ideal character . . . practical facts were neglected.”