At the start of his days as a fugitive, Booth shaved off his mustache in the vain hope of making himself less recognizable. At the time he was killed --all his facial hair was becoming visible.
Booth gave Officer John Parker a calling card, but that didn't happened in reality because Parker was at the saloon when Booth gave his calling card to Lincoln's personal valet and messenger, Charles Forbes. Parker was also in the box when Lincoln was attended by his doctors, but Parker was still at the saloon at the time of the shooting in real life.
John Wilkes Booth was at Ford's Theater before the Lincolns and their guests arrive, but he actually arrived one hour later after the Presidential Party arrived.
Lincoln's collar was intact, but it is actually cut off of his shirt by bystander, William Kent.
John Wilkes Booth and his henchmen were at the Surratt tavern discussing their plans to murder President Abraham Lincoln, Vice President Andrew Johnson, and Secretary of State William Seward before the Lincolns left for the carriage. According to some historical sources, the time was 8:45 when Booth and his henchmen were discussing their plans, just 15 minutes after the Lincolns and their guests arrived at Ford's Theater.
In one scene there is a wallpaper which features a pattern of cyphers consisting of the letters VRI and a royal crown. The letters stand for "Victoria Regina Imperatrix" which is Latin for "Victoria Queen Empress". It seems strange that such a royal motif would have been used in the USA. However even if someone would have wanted to decorate their walls with cypher of the British monarch in 1865, it would have been "VR". It was not until 1877 that Queen Victoria was given the title "Empress of India" when India was formally incorporated into the British Empire.
When Lewis Paine is stabbing Secretary Seward in his bed, at the right of the screen you can see a camera operator.
Laura Keene wasn't in the box when Leale attends Lincoln, but she actually made to the box to cradle Lincoln's head in her lap that her dress got blood.
Clara Harris, Major Rathbone's girlfriend, was wearing a long sleeved dress, but she actually wore a sleeveless dress in reality.
After Booth proclaimed that he will be the most famous man in America, he goes to the back of Ford's Theater with his horse, but he actually left his horse at the back of the theater. He also entered the theater through the front door at 10 minutes after 10 P.M.