Vital To Victory Vicksburg Fortress City Civil War

The Nation was divided, but both sides agreed: Vicksburg was Vital to Victory
To Confederate President Jefferson Davis, Vicksburg was the "nailhead that holds the South's two halves together."  President Abraham Lincoln remarked "Vicksburg is the key" to victory, and could be the north's lifeline into the south. 
As the federals closed in on the Fortress City, they were met by a ring of forts with over 170 cannon. The resulting battle would determine the war's outcome
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https://www.nps.gov/vick/index.htm?mobr=1