Factual error: Scarlett is seen walking on the main street on the way to the hospital. You can clearly see a light bulb in one of the street lights.
Revealing mistake: In the scene where Ashley is brought back wounded from the raid where Scarlett's husband Mr Kennedy was killed, Melanie grabs an oil lamp to follow the man carrying Ashley to the bedroom and you can see an electrical cord hanging down from it.
Continuity mistake: The shadow scene in which Scarlett and Melanie care for the wounded in the Atlanta hospital was filmed with two doubles. Since Leigh and de Havilland were standing at the wrong angle to cast the shadows, two stand-ins were positioned in front of the high-intensity light. The shadows of the doubles were reflected on the wall behind the stars, and the result was a stunning visual effect. Yet upon a closer look, the gestures of the stand-ins are not totally synchronised with the movements of the stars.
Other mistake: The credits for the Tarleton brothers in the opening credits have the twins switched with their actors. George Reeves doesn't play Brent, he plays Stuart. You know this because in the opening scene the two boys are talking about the party and asking Scarlett for dances, and George Reeves points at his brother and calls him "Brent."
Continuity mistake: In the scene showing guests arriving at the Wilkes' barbecue, you see buggies and carriages driving through the front gates and up the drive toward the Wilkes' home. The carriages clearly create shadows on the ground, but not on the stone pillars of the gates. This is because when the movie was filmed, there were no actual gates. The gates were later "painted" into the frame. Proving someone forgot to "paint" shadows onto the pillars.
Continuity mistake: When Scarlett is attacked in the woods on a bridge while on her way to the lumber mill the buggy very nearly goes off of the bridge backwards. Then Scarlett faints, but when the camera returns to the full shot of the buggy, suddenly it is squarely in the middle of the bridge and in no danger at all of falling over the edge.
Continuity mistake: While our protagonists flee from the burning Atlanta the carriage stops. A bearded soldier walks by carrying another man. A few moments later the camera focuses on a young man who collapses and is being picked up by exactly the same guy who was carrying him already. The mistake wouldn't be as pronounced if it weren't been one of the few instances where action by extras is highlighted.
Continuity mistake: When Rhett stops the carriage on the bridge at the turn for Tara, he pulls the brake to keep the carriage from moving. When Scarlett drives off in the carriage, she does not release the brake.
Continuity mistake: When Scarlett is attacked in the woods, Big Sam drives her carriage out of danger. When the scene cuts to a far shot of the carriage driving through the woods, Big Sam is no longer with her. She is driving it by herself.
Factual error: When Atlanta is in chaos, there is a shot of a fire engine rushing down the street. Two shots later is a wide shot of the street with a giant red and white radio tower visible in the distance.
Character mistake: Prior to the Scarlett's Pledge scenes, Mammy Informs Scarlett (while they're standing out side of Scarlett's father study door) "We ain't got nothing but radishes in the garden." The next scenes show Scarlett walking through the fence that surrounds the garden. walks up to where the radishes are growing, digs one up, wipes it off and starts to eat it. This actually is a carrot, not a radish.
Continuity mistake: In the scene where Bonnie and Rhett have just arrived back from London, Bonnie runs up the stairs to greet her Mom, arms flying all over the place. In the next shot, Bonnie is holding the kitten that Rhett bought her.