Excerpt: "Historical Times Encyclopedia of the Civil War" edited by Patricia L. Faust
From mid-Oct. 1862, Major General Ulysses S. Grant made several attempts to take Vicksburg. Following failures in the first attempts, the Battle of Chickasaw Bluffs, the Yazoo Pass Expedition, and Steele's Bayou Expedition, in the spring of 1863 he prepared to cross his troops from the west bank of the Mississippi River to a point south of Vicksburg and drive against the city from the south and east. Commanding Confederate batteries at Port Hudson, La., farther south prevented the transportation of waterborne supply and any communication from Union forces in Baton Rouge and New Orleans. Naval support for his campaign would have to come from Rear Admiral David D. Porter's fleet north of Vicksburg. Running past the powerful Vicksburg batteries, Porter's vessels, once south of the city, could ferry Federals to the east bank. There infantry would face 2 Confederate forces, one under Lieutenant General John C. Pemberton at Vicksburg and another around Jackson, Mississippi, soon to be commanded by General Joseph E. Johnston.
In Jan. 1863 Grant organized his force into the XI Corps under Major General John A. McClernand, the XV Corps under Major General William T. Sherman, the XVI Corps under Major General Stephen A. Hurlbut, and the XVII Corps under Major General James B. McPherson. Simultaneous with Grant's Vicksburg offensive, Major General Nathaniel P. Banks began his maneuvering along the Red River in Louisiana. Hurlbut's corps was subsequently transferred to New Orleans. With his 3 remaining corps, Grant began operations late in March. On the 29th and 30th McClernand's and McPherson's men, at Milliken's Bend and Lake Providence, northwest of Vicksburg, began working their way south, building a military road to New Carthage, La., preparatory to a move south to Hard Times, La., a village opposite Bruinsburg, Miss.
On the night of 16 Apr., at Grant's request, Porter took 1 2 vessels south past the Vicksburg batteries, losing 1 to Confederate fire. On 17 Apr. Grierson's Raid began. Led by Brigadier General Benjamin H. Grierson, Federal cavalry left La Grange, Tenn., for 16 days riding through central Mississippi to Baton Rouge, La., pulling away large units from Vicksburg's defense to pursue them. Porter, encouraged by light losses on his first try, ran a large supply flotilla past the Vicksburg batteries the night of 22 Apr. Sherman's troops, many at work on a canal project at Duckport, abandoned this work, joined in a last action along the Yazoo River, northeast of Vicksburg, and 29-30 Apr. made a demonstration against Confederate works at Haynes' Bluff and Drumgould's Bluffs, diverting more of Pemberton's force. Also on 29 Apr., as McClernand's and McPherson's troops gathered near Hard Times, Porter's fleet assailed Confederate batteries at Grand Gulf, 33 mi. southwest of Vicksburg, testing the Grand Gulf area as a landing site for Union troops. Though Porter found the guns there too strong, he had succeeded in further diverting Pemberton in Vicksburg.
Grant had originally determined that Rodney, Miss., would be the starting point of his invasion, but took the advice of a local slave and picked Bruinsburg instead. McClernand's and McPherson's corps were ferried east across the Mississippi from Hard Times 30 Apr. That day Grant sent word north for Sherman to follow McPherson's route south and join him.
On I May the Federal invasion force engaged the Confederates in the Battle of Port Gibson. Pemberton had just over 40,000 men assigned to the Vicksburg region. Since they were scattered throughout the area, chasing Grierson and wary of Sherman, few of them could be brought to bear against Grant on short notice. Defeated at Port Gibson, Pemberton's troops moved north. Grant, to Pemberton's confusion, pushed northeast. Sherman's corps joined him 8 May, and 12 May the engagement at Raymond was fought. Johnston took personal command of Confederates at Jackson, 15 mi northeast of Raymond, 13 May. On 14 May Federals quickly won an engagement at Jackson, cut off Johnston from Pemberton, and ensured the latter's isolation for the rest of the campaign. In 2 weeks Grant's force had come well over 130 mi. northeast from their Bruinsburg landing site.
Ordering Sherman to destroy Jackson's heavy industry and rail facilities, Grant turned west, roughly following the Southern Mississippi Railroad to Bolton, and 16 May fought the climactic combat of his field campaign, the Battle Of Champion's Hill. With the largest force he had yet gathered to oppose Grant, Pemberton nevertheless took a beating there and pulled his army into the defenses of Vicksburg. In a delaying battle at Big Black River Bridge, 17 May, Confederates crossed the Big Black, destroying their river crossings behind them. Undeterred, Federals threw up their own bridges and continued pursuit the next day.
Approaching from the east and northeast, McClernand's, McPherson's, and Sherman's corps neared the Vicksburg defenses 1 8 May, Sherman's veering north to take the hills overlooking the Yazoo River. Possession of these heights assured Grant's reinforcement and supply from the North. The next day Federals made the failed first assault on Vicksburg. The second assault, 22 May, was a disaster for Union forces, showed the strength of the miles of Confederate works arching east around the city, and convinced Grant that Pemberton could only be defeated in a protracted siege.
The siege of Vicksburg began with the repulse of the 22 May assault and lasted until 4 July 1 863. As the siege progressed, Pemberton's 20,000-man garrison was reduced by disease and starvation, and the city's residents were forced to seek the refuge of caves and bombproofs in the surrounding hillsides, Hunger and daily bombardments by Grant's forces and Porter's gunboats compelled Pemberton to ask for surrender terms 3 July. Grant offered none, but on the garrison's capitulation immediately paroled the bulk of the force. Many of these same men would later oppose him at Chattanooga.
Pemberton's surrender ended the Vicksburg Campaign. But during the siege, to the east Johnston had raised a 31,000 man force in the Jackson area. On 4 July, as Confederates were being paroled, Sherman moved his force to oppose this new threat. Sherman's march would result in the Siege of Jackson.