By Gary Gallagher, Ph. D., University of Virginia
Grant’s opponents were John C. Pemberton with his 32,000 men and Joseph E. Johnston, who had fought the Battle of Seven Pines in May 1862. Besides giving Johnston, overall command of a big section of the Western Theater, why did Jefferson Davis decide to deploy Pemberton who hadn’t demonstrated great ability in the civil war to command in a crucial place like Vicksburg?

Advantage for Grant
Johnston commanded about 16,000 Confederates in a small army, east of Vicksburg at Jackson, Mississippi. He was also technically, Pemberton’s superior. A crucial feature of the campaign was the failure of the Confederates to combine these two armies. They had potentially nearly 50,000 soldiers in Mississippi there, but they never got those two forces together to present a united front to Grant. Grant had the luxury, partially because he moved so effectively, of facing each of these Confederate forces in detail rather than facing a larger Confederate army all in one place.
Knowing Pemberton

Pemberton was an interesting character, a northerner, born in Pennsylvania. As West Pointer, he was veteran of the Mexican War, married to a Virginia woman in the late 1840s. It was his marriage to a Southerner that decided his lot with the Confederacy. A number of Northern officers who married Southern women fought with the Confederacy, and some Southern officers married to Northern women fought for the North. Pemberton was one of the Northerners who fought for the South.
He compiled less than a brilliant record early in the war. Part of his service was as commander in Charleston for some time. It was a mystery as to why Jefferson Davis selected John C. Pemberton to command in such a crucial place, Vicksburg. Davis thought Vicksburg was one of the most important places in the Confederacy, and he put a man in command there who hadn’t demonstrated great ability in the Civil War.
Some historians suggested that part of Davis’s thinking was that he needed a place to stick Gustave Toutant Beauregard, who also reported himself, able to take up duties again. Beauregard, who was a better choice for Vicksburg, ended up at Charleston, Pemberton’s old post, and Pemberton, a lieutenant general by October 1862, was now commanding the principal army in Vicksburg.
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Grant’s Unknown Whereabouts
After Sherman joined his army, Grant disappeared into the interior of the state of Mississippi. The North had no idea what was going on with Grant’s army until he showed up at Vicksburg days later. Lincoln, including Secretary of War Stanton and Henry W. Halleck did not know what Grant was doing for about two weeks.

During those two weeks, Grant marched 180 miles, fought and won four battles, and then reappeared at the outskirts of Vicksburg. During that period, he confused the Confederates by, first marching east into the interior of Mississippi. Instead of northward towards the city of Vicksburg, he marched away from it, towards Jackson. Grant’s idea was to defeat Joe Johnston first near Jackson, make sure that the Confederates couldn’t unite, and then turn back toward Vicksburg, which he did.
On May 12, the advance elements of Grant’s army defeated a small Confederate force in the Battle of Raymond, west of Jackson. Two days later, on May 14, Grant drove Johnston out of Jackson. Sherman and his troops destroyed a number of industrial facilities in Jackson, tore up the railroads, and destroyed the rolling stock. They did a quick job because Grant quickly turned west toward Vicksburg. Grant made sure, the Confederate forces were separated for some time and he headed toward Vicksburg. By that point, John Pemberton decided to strike Grant. He thought of interrupting Grant’s supply line but was not aware that Grant did not have a supply line. Pemberton’s idea was to slow him down but that was not to be.
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Pemberton’s unimagined Defeat
The two forces came together on May 16 in the decisive battle of that campaign at Champion’s Hill. Grant thoroughly defeated Pemberton in the battle. There were nearly 4,000 Confederate and about 2,500 Federal casualties, but the key thing was that Pemberton was pushed westward, back toward Vicksburg. On May 17 they fought again at the Big Black River, 10 miles east of Vicksburg. Again, Grant won the battle. It was another loss for Pemberton—1,700 Confederate casualties to just 200 Union casualties. Most of those Confederates were captured.
After the battle at Big Black River, Pemberton retreated into the defenses of Vicksburg. He did so despite the fact that Joseph E. Johnston had sent an appeal to him to not do that. Johnston understood that if Pemberton hunkered down in the defenses at Vicksburg Grant would lay siege to the place and the outcome would be Confederate defeat. Johnston tried to stop Pemberton from going to Vicksburg, but failed. Pemberton explained, that it was the most important point in the Confederacy to not be abandoned.
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Grant’s Plans for Victory and an Unexpected Loss
Grant achieved what he wanted to. Those in Grant’s army began to get a glimmer of what their commander was up to. But a lot of them, including William Tecumseh Sherman, who was an extremely bright person hadn’t understood what he was up to and how brilliantly Grant had been performing.
Grant’s army surrounded the stronghold at Vicksburg on the land side. The Union navy had a predominance on the water side. There was no Confederate navy at Vicksburg, no Confederate strength on the naval side. Grant thought that Pemberton’s troops were demoralized by their recent defeats at Champion’s Hill and the Big Black River and the frontal assaults would allow him to take Vicksburg quickly and avoid the necessity of a siege. He launched those assaults against the city on May 19 and 22, but failed completely with more than 4,000 casualties, as many casualties as he’d suffered in all the other battles leading up to Vicksburg.
Sobered by those losses, Grant decided that the only way to capture the place was to settle for a siege. Joseph Johnston understood there was only one way that this kind of siege could end, but the defenders and the citizens of Vicksburg put up an admirable struggle for six weeks. Threats of assaults all along the line kept the Confederate defenders and the civilians off guard in a state of constant anxiety.
Common Questions about the American Civil War
Lieutenant Colonel Pemberton was a northerner, born in Pennsylvania. A West Pointer, he was veteran of the Mexican War married to a Virginia woman in the late 1840s. Pemberton was one of the Northerners who fought for the South.
After the battle at Big Black River, Pemberton retreated into the defenses of Vicksburg, despite the fact that Joseph E. Johnston had sent an appeal to him, not to. Pemberton explained, that it was the most important point in the Confederacy to not be abandoned.
Grant thought that Pemberton’s troops were probably demoralized by their recent defeats and that would make seizing Vicksburg easier. But he was in for a surprise when Vicksburg put up a brave defense.