The incident below, related by a Union army veteran in A.L. Long's Memoirs of Robert E. Lee, is said to have taken place on July 3, 1863, the last day of the Battle of Gettysburg. It speaks of an American brotherhood that, in the end, transcended that terrible war.
I was at the battle of Gettysburg myself...I had been a most bitter anti-South man, and fought and cursed the Confederates desperately. I could see nothing good in any of them. The last day of the fight I was badly wounded. A ball shattered my left leg, I lay on the ground not far from Cemetery Ridge, and as General Lee ordered his retreat he and his officers rode near me.
As they came along I recognized him, and, though faint from exposure and loss of blood, I raised up my hands, looked Lee in the face, and shouted as loud as I could, "Hurrah for the Union!"
The general heard me, looked, stopped his horse, dismounted, and came toward me. I confess that I at first thought he meant to kill me. But as he came up he looked down at me with such a sad expression upon his face that all fear left me, and I wondered what he was about. He extended his hand to me, and grasping mine firmly and looking right into my eyes, said, "My son, I hope you will soon be well."
If I live to be a thousand years I shall never forget the expression on General Lee's face. There he was, defeated, retiring from a field that had cost him and his cause almost their last hope, yet he stopped to say words like those to wounded soldier of the opposition who had taunted him as he passed by. As soon as the general had left me I cried myself to sleep there upon the bloody ground.
(The American Patriot's Almanac)