Vicksburg campaign, in the American Civil War, the fighting (Nov., 1862–July, 1863) for control of the Mississippi River. The Union wanted such control in order to split the Confederacy and to restore free commerce to the politically important Northwest. New Orleans and Memphis fell to Union forces in the spring of 1862, but an attempt to take Vicksburg, Miss., by water failed (May–June). As a result the South still held 200 mi (320 km) of the river between Port Hudson, La., and Vicksburg. Early in Nov., 1862, Gen. Ulysses S. Grant, commanding the Dept. of the Tennessee, planned a converging assault on Vicksburg; Gen. William T. Sherman led an expedition down the river from Memphis to attack the city from the north, while Grant himself advanced overland from the east. However, Confederate cavalry under Earl Van Dorn and Nathan B. Forrest cut Grant's line of communications, forcing him to retreat, and Sherman was repulsed in the battle of Chickasaw Bluffs (Dec. 29, 1862). In Jan., 1863, Grant concentrated his army across the river from Vicksburg. He took over the command of John A. McClernand, who had succeeded Sherman. After several unsuccessful experiments to gain an approach to the seemingly impregnable city (Feb.–Mar., 1863), Grant in April began a brilliant movement to take it from the south. To divert the attention of the Confederate commander, John C. Pemberton, Grant left Sherman before the city and ordered a cavalry raid through central Mississippi. On the night of Apr. 16–17, David Dixon Porter ran gunboats and transports down the river past Vicksburg, and in the following days Grant marched his army south to meet the fleet and be transported across the river at Bruinsburg (c.30 mi/48 km S of Vicksburg). On May 1, McClernand and James B. McPherson defeated the Confederates at Port Gibson, forcing them to abandon their batteries at Grand Gulf, which Grant seized as a base. When Sherman joined him on May 7, 1863, Grant left Grand Gulf, marched northeast, and on May 12 defeated the Confederates at Raymond. At Jackson (May 14), he met Gen. Joseph E. Johnston, Confederate commander in the West, who retreated. Turning west toward Vicksburg, Grant defeated Pemberton in successive battles (May 16, 17) at Champion's Hill and at the bridge over the Big Black River, forcing him back into Vicksburg. After two unsuccessful attempts at storming the city's fortifications, Grant opened siege. With the Union forces between them, Pemberton and Johnston were unable to unite, and after about six weeks of gallant resistance Vicksburg's defenders surrendered on July 4, 1863. The fall of Port Hudson a few days later placed the Mississippi River entirely in Union hands.
See J. D. Milligan, Gunboats Down the Mississippi (1965); A. A. Hoehling, Vicksburg (1969).