Pickett's Charge was an infantry assault on July 3, 1863, during the Battle of Gettysburg. It was ordered by Confederate General Robert E. Lee as part of his plan to break through Union lines and achieve a decisive victory in the North. The charge was named after Major General George Pickett, one of the Confederate Army's division commanders. The assault was aimed at the center of the Union Army's position on Cemetery Ridge, which was believed to be a vulnerable point in the Union defenses. As the Confederate troops marched across nearly a mile of open ground, they came under heavy artillery and rifle fire from entrenched Union forces. The open terrain offered little cover, making the Confederate soldiers easy targets, and their ranks were quickly decimated. Although a small number of the Confederate soldiers managed to reach the Union lines and engage in hand-to-hand combat, they were ultimately overwhelmed.

The charge ended in a disastrous defeat for the Confederates, with more than half of the men involved either killed, wounded, or captured. Pickett's Charge marked the climax of the Battle of Gettysburg, and its furthest advance is called the "high-water mark of the Confederacy". The failure of the charge crushed the Confederate Army's hopes of winning a decisive victory in the North and forced General Lee to retreat back to Virginia. The charge has often been mythologized in American narratives about the Civil War, especially in the South.

Pickett's Charge was planned for three Confederate divisions, commanded by Maj. Gen. George Pickett, Brig. Gen. J. Johnston Pettigrew, and Maj. Gen. Isaac R. Trimble, consisting of troops from Lt. Gen. James Longstreet's First Corps and Lt. Gen. A. P. Hill's Third Corps. Pettigrew commanded brigades from Maj. Gen. Henry Heth's old division, under Col. Birkett D. Fry (Archer's Brigade), Col. James K. Marshall (Pettigrew's Brigade), Brig. Gen. Joseph R. Davis, and Col. John M. Brockenbrough. Trimble, commanding Maj. Gen. Dorsey Pender's division, had the brigades of Brig. Gens. Alfred M. Scales (temporarily commanded by Col. William Lee J. Lowrance) and James H. Lane. Two brigades from Maj. Gen. Richard H. Anderson's division (Hill's Corps) were to support the attack on the right flank: Brig. Gen. Cadmus M. Wilcox and Col. David Lang (Perry's brigade).

The target of the Confederate assault was the center of the Union Army of the Potomac's II Corps, commanded by Maj. Gen. Winfield S. Hancock. Directly in the center was the division of Brig. Gen. John Gibbon with the brigades of Brig. Gen. William Harrow, Col. Norman J. Hall, and Brig. Gen. Alexander S. Webb. On the night of July 2, Commander of the Potomac Army George Meade correctly predicted to Gibbon at a council of war that Lee would try an attack on Gibbon's sector the following morning. To the north of this position were brigades from the division of Brig. Gen. Alexander Hays, and to the south was Maj. Gen. Abner Doubleday's division of the I Corps, including the 2nd Vermont Brigade of Brig. Gen. George J. Stannard and the 121st Pennsylvania under the command of Col. Chapman Biddle. Meade's headquarters were just behind the II Corps line, in the small house owned by the widow Lydia Leister.

The specific objective of the assault has been the source of historical controversy. Traditionally, the "copse of trees" on Cemetery Ridge has been cited as the visual landmark for the attacking force. Historical treatments such as the 1993 film Gettysburg continue to popularize this view, which originated in the work of Gettysburg Battlefield historian John B. Bachelder in the 1880s. However, recent scholarship, including published works by some Gettysburg National Military Park historians, has suggested that Lee's goal was actually Ziegler's Grove on Cemetery Hill, a more prominent and highly visible grouping of trees about 300 yards (270 m) north of the copse.

The much-debated theory suggests that Lee's general plan for the second-day attacks (the seizure of Cemetery Hill) had not changed on the third day, and the attacks on July 3 were also aimed at securing the hill and the network of roads it commanded. The copse of trees, currently a prominent landmark, was under ten feet (3.0 m) high in 1863, visible to a portion of the attacking columns only from certain parts of the battlefield.

From the beginning of the planning, things went awry for the Confederates. While Pickett's division had not been used yet at Gettysburg, A. P. Hill's health became an issue and he did not participate in selecting which of his troops were to be used for the charge. Some of Hill's corps had fought lightly on July 1 and not at all on July 2. However, troops that had done heavy fighting on July 1 ended up making the charge.

Although the assault is known to popular history as Pickett's Charge, overall command was given to James Longstreet, and Pickett was one of his divisional commanders. Lee did tell Longstreet that Pickett's fresh division should lead the assault, so the name is appropriate, although some recent historians have used the name Pickett–Pettigrew–Trimble Assault (or, less frequently, Longstreet's Assault) to more fairly distribute the credit (or blame). With Hill sidelined, Pettigrew's and Trimble's divisions were delegated to Longstreet's authority as well. Thus, Pickett's name has been lent to a charge in which he commanded 3 out of the 11 brigades while under the supervision of his corps commander throughout.