[President Lincoln, United States Headquarters, Army of the Potomac, near Antietam]

Twenty-six thousand soldiers were killed or wounded in the Battle of Antietam on September 17, 1862, after which Confederate General Robert E. Lee was forced to retreat to Virginia. Just two weeks after the victory, President and Commander-in-Chief Abraham Lincoln conferred with General McClernand and Allan Pinkerton, Chief of the nascent Secret Service, who had organized espionage missions behind Confederate lines.

Lincoln stands tall, front and center in his stovepipe hat, his erect and commanding posture emphasized by the tent pole that seems to be an extension of his spine. The other men stand slightly apart in deference to their leader, in postures of allegiance with their hands covering their hearts. The reclining figure of the man at left and the shirt hanging from the tree are a reminder that, although this is a formally posed picture, Lincoln's presence did not halt the camp's activity, and no attempts were made to isolate him from the ordinary circumstances surrounding the continuing military conflict.