"The failure to crush the Federal army in Pennsylvania in 1863, in the opinion of almost all of the officers of the Army of Northern Virginia, can be expressed in five words - the absence of the cavalry." - Confederate General Henry Heth

As Robert E. Lee's army moved into Pennsylvania in June 1863, Stuart's cavalry screened his movements, thereby engaging in the more traditional cavalry roles. This time, however, as Lee began his march north through the Shenandoah Valley in western Virginia, it is highly unlikely that is what he wanted or expected.

Before setting out on June 25, the methodical Lee gave Stuart specific instructions as to the role he was to play in the Pennsylvania offensive. As the eyes of the army, the cavalry was to guard the mountain passes with part of his force. Maintaining contact with Ewell's army as it advanced towards Harrisburg.

Instead of taking the most direct route north near the Blue Ridge Mountains, however, Stuart chose a much more ambitious course of action. Stuart decided to march his three best brigades between the Union army and Washington. To complicate matters even more, as Stuart set out on June 25 on what was probably a glory-seeking mission, he was unaware that his intended path was blocked by columns of Union infantry that would invariably force him to veer farther east than he or Lee had anticipated. Ultimately, his decision would prevent him from linking up with Ewell as ordered and deprive Lee of his primary cavalry force as he advanced deeper and deeper into unfamiliar enemy territory. According to Halsey Wigfall (son of Confederate States Senator Louis Wigfall) who was in Stuart’s infantry, "Stuart and his cavalry left [Lee’s] army on June 24 and did not contact [his] army again until the afternoon of July 2, the second day of the [Gettysburg] battle."