When was the Battle of Vicksburg?
The Battle of Vicksburg took place in May and June of 1863; until the Confederate army surrendered Vicksburg on July 4.
The Battle of Vicksburg was a major battle in the Civil War in Vicksburg, Mississippi. The Confederates had their only stronghold there. General Grant's plan was to gain control of Vicksburg and the Mississippi River. General Pemberton was running out of food and supplies so he surrendered. Because the Union took control of the Mississippi River it split the South into two. That's how the Battle of Vicksburg is important in the Civil War.
Better said was the "battles to capture Vicksburg". At least three Union attempts failed to actually capture the city fortress of Vicksburg. Only via a siege was the city captured. And, yes this at last gave the Union full control of the Mississippi River. This was now the western base from which to launch assaults on either side of the river.