Edwin McMasters Stanton (December 19, 1814 – December 24, 1869) was an American lawyer and politician who served as Secretary of War under the Lincoln Administration during most of the American Civil War. Stanton's management helped organize the massive military resources of the North and guide the Union to victory. He also organized the manhunt for Lincoln's killer, John Wilkes Booth. However, he was criticized by many Union generals for perceived over-cautiousness and micromanagement.
After Lincoln's assassination, Stanton remained as the Secretary of War under the new President Andrew Johnson during the first years of Reconstruction. He opposed the lenient policies of Johnson towards the former Confederate States. Johnson's attempt to dismiss Stanton ultimately led to President Johnson being impeached by the House of Representatives. Stanton returned to law after retiring as Secretary of War, and in 1869 was nominated as an Associate Justice of the Supreme Court by Johnson's successor, Ulysses S. Grant; however, he died four days after his nomination was confirmed by the Senate.