Vicksburg sat on 200-foot bluffs above a hairpin bend of the Mississippi, the last major obstacle to Union control of the river under the Anaconda Plan. Its defender, Lieutenant General John C. Pemberton, was a Pennsylvanian with two brothers in the Union Army, caught between Joseph E. Johnston’s advice to abandon the city and Jefferson Davis’s order to hold it. He withdrew his roughly 18,000 men behind a six-and-a-half-mile ring of redoubts and lunettes as Ulysses S. Grant closed in after a string of victories.

Grant’s assaults on May 19 and May 22 failed, the second prolonged by John McClernand’s misleading report that he had taken two forts, which cost over 3,000 Union casualties and later his command. Grant then chose to out-camp the enemy, ringing the city with as many as 77,000 men while 22,000 shells drove civilians into more than 500 clay caves. Hunger, disease, a failed Confederate attack at Milliken’s Bend and a mine blown under the 3rd Louisiana Redan followed, until Pemberton timed his surrender for July 4, 1863, and Grant paroled the garrison rather than ship it north.

• Union soldiers called the cave-dwelling town the Prairie Dog Village.
• Before the May 22 assault, troops chanted hardtack as Grant rode past.
• During a truce on May 25, men from both armies traded coffee and tobacco while burying the dead.
• Newly enlisted United States Colored Troops held the depot at Milliken’s Bend in hand-to-hand fighting.
• Confederates rolled lit artillery shells into the 2,200-pound mine crater, and souvenir hunters whittled away the surrender oak.