Edward Lyon Buchwalter took part in the engagements between Union and Confederate forces during the Vicksburg Campaign at the Battle of Thompson's Hill, the Battle of Port Gibson (May 1, 1863, near Port Gibson, Miss.), Battle of Raymond (May 12, 1863, near Raymond, Miss.), Battle of Champion Hill (May 15, 1863, on Barker's Creek, Hinds Co., Miss.), Battle of Big Black River Bridge (May 17, 1863, Hinds County, Miss) and the assaults at the Battle of Vicksburg (at Vicksburg, Mississippi), and thus had his full share of intensive warfare. Vicksburg was the site of the Siege of Vicksburg (May 18 – July 4, 1863), an important battle in which the Union forces gained control of the entire Mississippi River. The battle consisted of a long siege, which was necessary because the town was on high ground, well fortified, and difficult to attack directly. The capture of Vicksburg and the simultaneous defeat of General Robert E. Lee at Gettysburg marked the turning point in the Civil War.