Please limit your eNotes queries to one question per post. I have edited your question accordingly.
Robert E. Lee's mighty Army of Northern Virginia was fresh off another victory over the much larger Union army following the bloody battle of Chancellorsville. His next plan was to invade the Northern states in the hope of possibly capturing Washington, D.C. and ending the war. However, during the march northward, Lee's cavalry commander, J.E.B. Stuart, was incommunicado for much of the time, and Lee was uncertain of his enemy's position. He never intended to force a battle at Gettysburg, but when one of his brigade commanders discovered that there was a surplus of shoes available in the town, it was decided that a portion of the army would detour there. Many of Lee's men were marching barefoot, so the shoes would prove invaluable on the march through Pennsylvania and into Maryland. However, the Confederates were surprised by Union troops who had discovered their whereabouts, and a battle ensued. Lee decided after surveying the terrain that Gettysburg would be a good place to stand and fight. This would prove to be one of the worst decisions of his military career.