Battle of Gettysburg Begins in Pennsylvania

Context

By the spring of 1863 the American Civil War had entered its third year. Confederate General Robert E. Lee’s Army of Northern Virginia had recently won a striking victory at Chancellorsville, but the triumph came at the cost of Lieutenant General Thomas J. “Stonewall” Jackson. Lee reorganized his army into three corps under Lieutenant Generals James Longstreet, Richard S. Ewell, and A. P. Hill. Seeking to relieve pressure on war-weary Virginia, obtain supplies from untouched Northern farms, and possibly influence political sentiment in the Union, Lee launched his second invasion of the North in early June.

What Happened

On June 30 a Confederate brigade under Brigadier General J. Johnston Pettigrew approached Gettysburg on a foraging mission and spotted Union cavalry under Brigadier General John Buford. The next morning Major General Henry Heth’s division advanced in force. Buford’s troopers slowed the Confederate advance along McPherson Ridge, buying time for Union infantry. Major General John F. Reynolds, commanding the I Corps, arrived with reinforcements and was killed early in the fighting. Additional Union troops from the XI Corps joined the defense, but Confederate pressure from Hill’s and Ewell’s corps mounted throughout the afternoon.

Aftermath

By evening Union forces had fallen back through the streets of Gettysburg and established a defensive line on Cemetery Hill and Culp’s Hill south of town. Lee arrived on the field and declined an immediate assault on the heights. Both armies continued to concentrate; by the following morning the Union line resembled a fishhook anchored on those hills, while Confederate forces prepared to attack its flanks.

Legacy

The engagement that began on July 1 became the bloodiest battle in American history up to that time and marked the northernmost point of major Confederate operations in the East. Union victory ended Lee’s invasion, lifted Northern morale after earlier setbacks, and allowed President Abraham Lincoln to redefine the war’s purpose in his Gettysburg Address four months later. Historians widely regard the battle as the high-water mark of the Confederacy and a turning point that preserved the United States.