President Lincoln was killed by John Wilkes Booth, an actor and part of a conspiracy to aid the Southern cause. This occurred five days after Lee's surrender to Grant at Appomatox Courthouse. Booth did not act alone; he and several other conspirators had met for weeks planning to assassinate Lincoln, Vice President Andrew Johnson, and Secretary of State William Seward. The belief of the group was that by literally decapitating the federal government, they would aid the cause of the South and deliver victory to the South in the civil war. Only the completion of Lincoln was completed. Seward's intended assassin, Louis Powell, entered Seward's home pretending to deliver medicine for a carriage accident the latter had recently suffered. He forced his way past a servant and attempted to cut Seward's throat; but failed because of a device strapped to Seward's jaw intended to help him heal from his injury. He did manage to stab Seward's son. Johnson's assassin called at Johnson's hotel, and left a card for him when Johnson was not in. He went to a nearby tavern, got drunk and lost his nerve.
Booth went to Ford's theater early in the day and drilled a hole through the wall to the Presidential box to create the image of a bullet fired through the wall. Later in the evening, he managed to ease into the booth when Lincoln's guard was next door at a tavern. Booth often acted in the theater, so access was not an issue for him. Lincoln was dozing during the play ("Our American Cousin") when Booth shot him at point blank range in the head. Booth escaped by jumping from the stage and ridng a waiting horse into Virginia territory. He was cornered several days later and shot while attempting to surrender. The other conspirators and the owner of the tavern where they met, Mary Surratt, were all hanged.
There has been speculation for many years that Lincoln's Secretary of War, Edwin Stanton was part of the plot. No conclusive evidence of Stanton's involvement has been discovered.