The Vicksburg Campaign is a series of maneuvers and battles in the Western Theater of the American Civil War directed against Vicksburg, Mississippi, a fortress city that dominated the last Confederate-controlled section of the Mississippi River.

The Union Army of the Tennessee under Maj. Gen. Ulysses S. Grant gainscontrol of the river by capturing this stronghold and defeating Lt. Gen. John C. Pemberton's forces stationed there.

The campaign consists of many important naval operations, troop maneuvers, failed initiatives, and eleven distinct battles from December 26, 1862, to July 4, 1863.

Military historians divide the campaign into two formal phases: Operations Against Vicksburg (December 1862 – January 1863) and Grant's Operations Against Vicksburg (March–July 1863).

Grant initially plans a two-pronged approach in which half of his army, under Maj. Gen. William Tecumseh Sherman, will advance to the Yazoo River and attempt to reach Vicksburg from the northeast, while Grant will take the remainder of the army down the Mississippi Central Railroad.

Both of these initiatives fail.

Grant conducts a number of "experiments" or expeditions—Grant's Bayou Operations—that attempt to enable waterborne access to the Mississippi south of Vicksburg's artillery batteries.

All five of these initiatives fail as well.

Finally, Union gunboats and troop transport boats run the batteries at Vicksburg and meet up with Grant's men, who had marched overland in Louisiana

On April 29 and April 30, 1863, Grant's army crosses the Mississippi and lands at Bruinsburg, Mississippi.

An elaborate series of demonstrations and diversions fool the Confederates and the landings occur without opposition.

Over the next seventeen days, Grant maneuvers his army inland and wins five battles, captures the state capital of Jackson, Mississippi, and assaults and lays siege to Vicksburg.

After Pemberton's army surrenders on July 4 (one day after the Confederate defeat at Gettysburg), and when Port Hudson surrenders to Maj. Gen. Nathaniel P. Banks on July 9, Texas and Arkansas are effectively cut off from the Confederacy, and the Mississippi River is once again open for northern commerce to reach the Gulf of Mexico, and as a supply line for the Union Army.

Grant's Vicksburg Campaign is studied as a masterpiece of military operations and a major turning point of the war.