On July 4 1863 general Ulysses S. Grant defeated the confederate army at Vicksburg Mississippi and the union took control of this city why was this an important victory for the union?

Vicksburg and Port Hudson, two fortified ports on the Mississippi River, were important during the Civil War for their strategic location. Should the Union be able to take these Confederate strongholds, they would finally command the Mississippi River in its entirety. So long as these strongholds remained in Confederate hands, the South would remain unified and defiant of the Northern attempt to break it in two.