After winning at Chancellorsville, Gen. Robert E. Lee chose to keep the initiative by shifting the Army of Northern Virginia away from Fredericksburg and toward the Shenandoah Valley. The move set up a second Confederate invasion of the North, aimed at drawing Union forces away from Virginia and putting pressure on Northern politics and resources.
Union cavalry attacked Confederate cavalry near Brandy Station in one of the largest cavalry fights of the war. Although Confederate cavalry held the field, the clash signaled that Union horsemen were becoming more aggressive and made it harder for Lee to keep his army’s movements hidden.
Confederate forces under Lt. Gen. Richard S. Ewell struck the Union garrison around Winchester in the Shenandoah Valley. The Confederate victory helped clear major Union resistance from the Valley, opening a safer route for Lee’s army to move north.
As Union resistance in the Shenandoah Valley collapsed, Lee’s army pushed north and began crossing the Potomac River. This marked the invasion phase of the campaign, shifting major operations onto Northern soil and forcing the Union Army of the Potomac to follow.
Union cavalry tried to break through the Confederate cavalry screen near gaps in the Blue Ridge Mountains. Fighting at Aldie delayed the Union effort to learn where Lee’s main force was headed, buying time for the Confederate infantry moving north behind the mountains.
Cavalry engagements spread to Middleburg as Union forces continued probing for Lee’s army. The continued clashes helped Confederate cavalry slow Union reconnaissance and kept Lee better protected while his army advanced toward Pennsylvania.
Union cavalry made another determined push at Upperville to pierce the Confederate screen. These fights around Aldie, Middleburg, and Upperville helped prevent Union cavalry from quickly locating and disrupting Lee’s main movement north.
As Lee’s army spread across Pennsylvania, Union command changed hands. Maj. Gen. George G. Meade replaced Maj. Gen. Joseph Hooker and continued moving the Army of the Potomac north, focused on staying between Lee and Washington, D.C.
With Union forces closing in, Lee directed his scattered corps to concentrate using road networks that converged on Gettysburg. This decision set the stage for a major battle, as both armies’ movements began pulling them toward the same crossroads region.
Confederate cavalry under J.E.B. Stuart, moving on a long raid around the Union army, clashed with Union cavalry near Hanover, Pennsylvania. The fight added delays and confusion for Stuart, and the raid’s larger effect was that Lee lacked timely cavalry reconnaissance as the main armies neared Gettysburg.
The armies collided near Gettysburg on July 1 as Confederate and Union forces engaged north and west of the town. The day’s fighting drew in more troops and helped shape a larger battlefield, as Union forces established a strong defensive position on high ground south of Gettysburg.
Stuart’s cavalry briefly fought Union militia at Carlisle, Pennsylvania, and then moved on. The action reflected how far Stuart’s command had ranged during the raid and how late it was arriving back to Lee during the crucial opening of the Gettysburg battle.
On July 2, Confederate assaults struck hard at the Union left and right, including intense fighting at places like Little Round Top, Devil’s Den, and Culp’s Hill. The Union line bent in places but did not break, keeping a continuous defensive position for the next day.
On July 3, Lee ordered a large assault against the Union center after an artillery bombardment. The attack—often called Pickett’s Charge—failed, and the Confederate army suffered heavy losses, marking a turning point that ended Lee’s attempt to win a major battle on Northern soil.
With the battle lost, Lee began moving his army back toward Virginia, slowed by rain, damaged roads, and long wagon trains carrying wounded and supplies. Meade pursued but moved cautiously, and smaller actions erupted along the retreat routes as Union cavalry tried to disrupt the Confederate withdrawal.
Union cavalry struck parts of the Confederate retreating wagon trains near Monterey Pass during the night of July 4–5. The fighting damaged or captured wagons and prisoners, showing how vulnerable Lee’s army was during its withdrawal through narrow mountain routes and bad weather.
Lee reached the Potomac River but could not immediately cross because high water and lost bridging equipment limited options. The Confederate army entrenched defensively to protect potential crossings while Meade’s forces closed in, creating a tense pause where a major Union attack was possible.
As the river dropped, Lee’s army crossed the Potomac after dark and escaped into Virginia. Union cavalry attacked the Confederate rearguard near Falling Waters, but the main Confederate force got away—ending the campaign with Lee’s invasion repulsed and the war’s momentum shifting toward the Union.
Gettysburg Campaign (June–July 1863)