Who commanded the Union Army of the Potomac at Gettysburg?

George G. Meade commanded the Union Army of the Potomac at Gettysburg. He took command only three days before the battle began, replacing Joseph Hooker on 28 June 1863.

Meade quickly concentrated the army near Gettysburg, Pennsylvania, where it met Robert E. Lee's Army of Northern Virginia from 1 to 3 July. He adopted a strong defensive position, shaped roughly like a fishhook, and relied heavily on capable corps commanders including John F. Reynolds and Winfield S. Hancock. Union forces held their line through fierce fighting and repulsed Pickett's Charge on 3 July.

The common mix-up is that Reynolds and Hancock played crucial battlefield roles, but neither was the army's overall commander. Hooker had led the Army of the Potomac earlier in the Gettysburg campaign, while Meade was the commander during the battle itself. The Union victory halted Lee's second invasion of the North and became a major turning point in the Civil War.