The siege of Vicksburg was a decisive Union victory that lead to significant casualties to the Confederate Army and the final surrender of 29,495 soldiers. The Confederate Army was outnumbered more than 2-to-1. The battle started on May 18, 1863 and eventually ended in Pemberton’s surrender on July 4th, the day after Lee’s defeat at Gettysburg. The siege started with a series of failed attacks by Union forces over difficult terrain. Attempts to disrupt Union supply lines failed and allowed them to continue the siege. The eventual lack of supplies and food in Vicksburg finally resulted in extreme malnutrition, and significant spread of disease among the ranks amid a constant barrage of cannon fire. In addition, the people of Vicksburg were forced to live in holes dug out in hillsides because of damages caused by Union artillery.