Final answer:
General Ulysses S. Grant's campaign down the Mississippi River culminated in the Siege of Vicksburg, resulting in a pivotal Union victory that secured control over the Mississippi, split the Confederacy, and reinforced Grant's leadership stature.
Step-by-step explanation:
As General Ulysses S. Grant moved down the Mississippi River, he led the Union forces in a strategic campaign to control the river and split the Confederacy in two. By using his Army of the Tennessee, Grant forced Pemberton and the Army of Vicksburg into retreat all the way to Vicksburg, Mississippi, a vital Confederate stronghold. Despite initial failures in capturing the city, Grant's persistency and tactical maneuvering resulted in the siege and eventual surrender of Vicksburg on July 4, 1863, dealing a significant blow to Confederate defensive capabilities and giving the Union complete control of the Mississippi River. This victory, alongside the Union triumph at Gettysburg, marked a turning point in the Civil War.
The capture of Vicksburg not only undermined Confederate morale but also ensured that Confederate forces could never again mount a strong offensive in the Western Theatre. Grant's victory at Vicksburg elevated his stature, leading to Lincoln's recognition of him as a key military leader. Grant continued to apply force across multiple fronts, moving towards total war, which eventually led to the end of the war with Confederate surrender in 1865.