Who said "Vicksburg is the key to the South."?

This quote is attributed to William Tecumseh Sherman.

Vicksburg is the key to the South. - William Tecumseh Sherman

"Vicksburg is the key to the South."

William Tecumseh Sherman

Military General American 1820–1891

"War is cruelty, and you cannot refine it."

"I am tired and sick of war."

"You cannot qualify war in harsher terms than I will."

"There is many a boy here today who looks on war as all glory, but boys, it is all hell."