When John Wilkes Booth is in the corridor outside the President's box preparing to assassinate Abraham Lincoln, he draws and cocks his handgun then enters the box with the gun in his hand. Yet once inside the box, he reaches into his coat with the same hand (now empty) and draws out the gun again.
The position and condition of the flag on the left-hand side of Lincoln's box at Ford's Theater varies between shots. In the first long shot after Elsie points out Booth, it is hanging downwards from the middle, whereas in the shots immediately before and after, it is shown draped across the front of the left-hand railing. Similarly, after Booth shoots Lincoln and jumps from the box, the flag falls to the left-hand side of the box and an audience member is later shown pulling it down twice.
The position of the window in the small cabin changes.
The North would never try to hang a Southern Colonel just for fighting in a battle against Union troops.
The Ku Klux Klan never fought or won any battles with federal troops, black or white.
Ninety minutes into the film - although Austin Stoneman learns of the death of Lincoln while indoors, a sudden gust of wind causes a piece of paper on his desk to fly upward. It also ruffles the clothing of Stoneman's maid, thus revealing that this shot was filmed outside (employing the sun for lighting) rather than indoors, as the set depicts.
During the fight in the saloon between the white man & black men, the side wall of the saloon moves when someone comes in contact with it.
Car tire tracks are visible in the KKK segment.
Near the end of the film Lillian Gish and Miriam Cooper are rescued and lead back into town. Once they arrive a production assistant in modern dress can clearly be seen grabbing the reins of their horses.
The South Carolina coastline does not have bluffs overlooking the ocean.