What was the overcome of the battle siege of Vicksburg?
Liberation of the Mississippi and cutting-off of Confederate units to the West of the river.
Answer The Battle of Champion's Hill, just east of Vicksburg, was fought on 16 May 1863. This battle was fought out in the open and was a set-back for the Confederates. This forced them to return to the defenses of Vicksburg, which began the siege. The siege ended when General Pemberton surrendered Vicksburg on 3 July.
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.