Abraham Lincoln (February 12, 1809-April 15, 1865) was the sixteenth President of the United States. As Commander in Chief of the United States, he led the Union during the Civil War. On April 15, he was shot in the back of the head at Ford's Theater by John Wilkes Booth, and died shortly after from his wounds. Allan Pinkerton (25 Aug. 1819-1 July 1884) Asked by General McClellan to gather intelligence against Confederate enemies at the start of the Civil War. He headed an army spy system in Virginia, called the Secret Service, under the name Major E.�J. Allen. After General McClellan was dismissed in 1862, Pinkerton returned to his private detective business, the National Detective Agency.