Vicksburg During the Civil War (1862-1863): A Campaign; A Siege. When Vicksburg fell to Union troops on July 4, 1863, the Confederacy lost its last chance to control the Mississippi River.
The Civil War was fought in thousands of different places, from southern Pennsylvania to Texas; from New Mexico to the Florida coast. The majority of the fighting took place in the states of Virginia and Tennessee.
Union armies had gained two important victories at about the same time. ... The day after the battle of Gettysburg, Union forces defeated Confederate forces at Vicksburg, Mississippi. This victory gave them control of the Mississippi River. And it split the states of the Confederacy.
achieved through a deadly combination of resource superiority and combined arms strategy, the Union’s hard-won gains on the nation’s rivers were instrumental to overall victory in the war.
The geography faced by the western campaigners was quite different from that of their counterparts in the east. Roads were poorer, railroads were fewer, and much of the countryside was untamed. To add to these hazards, the western theater dwarfed the east in terms of square mileage—the west comprised some 385,000 square miles of potential battleground compared to around 95,000 miles in the east.
hope this helps