President Abraham Lincoln called Vicksburg the key to ending the war, because control of the lower Mississippi River would let the United States move agricultural products to world markets, split the South, and sever its supply lines. In the spring of 1863, Major General Ulysses S. Grant launched the Army of the Tennessee on a series of maneuvers and battles to pocket Vicksburg. The campaign involved deception and counter-intelligence, rapid marches, naval actions, a large-scale amphibious crossing, and fighting in difficult terrain and harsh climate. Grant's invading force carried war into the interior of the Deep South and eventually captured Vicksburg and an entire Confederate army, reopening the Mississippi River.
