Up the Potomac Without a Clue

Confederate General Robert E. Lee's goal in the weeks before Gettysburg was for his troops to surprise the Union Army north of the Potomac, and weaken it enough to force peace talks.

Normally, Lee relied on General J.E.B. Stuart's cavalry to provide necessary intelligence: where the enemy was, how many there were, and how prepared they appeared to be. Stuart had been sent across the Potomac ahead Lee and had been out of contact with his commander, and as Lee approached Gettysburg,

…his lack of information irritated him. Ordinarily, in Virginia, no sooner would he hear the challenge of distant guns than a courier would ride up with a dispatch from Stuart explaining what was afoot, but now - where was Stuart and what did the firing mean? Lee could not altogether conceal his impatience and admitted frankly that he had been in the dark since he had crossed the Potomac. (Source: Freeman)

Lee called for another of his generals, James Patton Anderson, to ask if he had heard from Stuart. No, Anderson told him, "In the absence of reports from him, I am in ignorance as to what we have in front of us here."

Anderson had no information that Lee had not already received. After a few more words, he left Anderson and started onward again toward the sound of the guns, the opening guns of Gettysburg…

… Lee galloped toward Gettysburg like a blinded giant. He did not know where the Federals were, or how numerous they might be. … With no cavalry to inform him, he could not tell what calamity he might invite by advancing at all, or what opportunity he might lose by advancing cautiously. Never had he been so dangerously in the dark. (Source: Freeman)

Lee continued towards Gettysburg, and eventually committed his troops to attacks that would turn the tide against the South. Historians debate, and will continue to debate, whether later decisions could have made up for Lee's initial ignorance of the the Union's true strength in and around Gettysburg. But many agree that his advance without the intelligence normally provided by Stuart's cavalry was a major blunder, and one that may have determined the eventual outcome of the war.

[Source: Douglas S. Freeman's R.E. Lee is in the public domain and is transcribed here.]