Continuity mistake: After Bill the Butcher stabs and beats Amsterdam's face badly (and brands him with a hot knife) notice how as time passes the wounds heal then reappear in varying degrees of severity. This is particularly true with the branding, which is almost absent by the end.
Continuity mistake: At several times during the movie, Butcher Bill's glass eye changes to what looks like a normal eye.
Continuity mistake: After Jenny gets mugged at the dock, the shot shows her pulling herself to a standing position on a crate. In the next shot, from farther back and up high, she is crawling over to the crate she just pulled herself up on. (02:20:55)
Continuity mistake: When Amsterdam arrives in New York City and is talking to his new friend, the bag he is holding switches from being held under his arm (camera shot from front) to being carried on his back (camera shot from the back). This happens at least four times in a row during the same scene. (00:22:55)
Continuity mistake: As someone pointed out earlier, the poster for the commemoration of the Five Points battle claims to be the 16th anniversary, but the date shows 1863 -- 17 years after the 1846 battle. To further add to the confusion, when William Cutting is talking to Amsterdam in the bedroom after the night at the brothel, he says, "I killed the last honorable man [Priest Vallon] 15 years ago [in the Five Points battle]." So which is it? 15, 16, or 17 years? (00:02:42)
Continuity mistake: The amount and position of the blood on Amsterdam's neck changes during the first fight with Jenny after he discovers she's a turtledove. (00:49:05)
Continuity mistake: At their first encounter after Amsterdam's return to New York, Bill asks him to come closer. Amsterdam comes around the post he was leaning on, then the camera cuts to Priest Vallon's picture, and when Bill says it's close enough you see Amsterdam coming around the same post again. (00:35:15)
Continuity mistake: When Amsterdam just met up with Jenny after she stole from the house, he is holding a handkerchief to his neck were he was cut. Then the camera view changes and his arm isn't there and it was too quick for him to move his arm. (00:50:20)
Continuity mistake: When Monk gives an election speech we see Amsterdam and his buddies standing at a distance in front of a house. When the camera angle changes in mid-sentence Amsterdam is standing in the first row of the audience. (02:05:25)
Continuity mistake: In the scene where Bill is cutting up the pig and is about to show Amsterdam the "kill" spots, he wraps up a piece of the pig for an old woman standing nearby. He throws the meat to Amsterdam to give to her and then reaches to unsheath a knife strapped to his right side. After Amsterdam gives the woman the meat and turns back around the shot cuts back to Bill and he is seen unsheathing the same knife he was holding seconds before.
Continuity mistake: During the theater scene a man tries to murder Bill the Butcher but Amsterdam saves his life. As Amsterdam is wrestling with the culprit his hat falls off but in the next shot it's back on, then off again.
Continuity mistake: When Jenny tells Amsterdam that she's leaving for California, she is seen walking through a stone walkway. The camera angle changes and she is seen just turning around a corner and the walkway is nowhere to be seen.
Continuity mistake: The moment when Bill attacks Vallon is very badly edited. There's a shot of Bill raising his cleaver, and it must be at Vallon because he had his eyes fixed on him already for a while. Then you see Vallon's arm crushed by a halberd, then again Bill staring at Vallon, then Vallon turning around, unharmed as it seems, and finally Bill slashing Vallon with his cleaver. (00:09:55)
Continuity mistake: When Amsterdam meets Jenny for the second time he is seen stealing what looks like an apple and is in his right hand. When she runs away he doesn't have the apple, but when the when the shot is on Amsterdam the apple reappears for him to throw it to the ground. (00:45:30)
Continuity mistake: When Jenny rubs her fingers over the old scars on Amsterdam's chest, you can see light under the tips of the scars as if they peeled up. (01:05:50)
Continuity mistake: When Amsterdam and Jenny continue talking after Bill has just left them in the bedroom, Jenny's hands keep shifting from both hands on her chest to just one hand between shots. (01:28:45)
Continuity mistake: Jenny pokes Amsterdam with her knife on the right side of the neck as he is trying to retrieve his medallion from her. Shortly afterwards, while walking back with her, he is seen dabbing the left side of his neck in two different shots, one of them pretty lengthy. (00:50:00)
Continuity mistake: When Amsterdam tries to kill the butcher and fails, the butcher straddles Amsterdam on a table and tosses a cleaver in the air. The cleaver rotates counter-clockwise so that the blade is rotating backward; however, when the cleaver lands, it is rotating clockwise so that the blade sticks into the wooden table. This would be impossible the way the cleaver is tossed into the air with a back-handed flip. (01:42:15)
Suggested correction: It is possible, if it falls quick enough. Doesn't matter where it rotates, if it is blade down at the moment of touching the table - it will stick.
Continuity mistake: At the end of the fight in the bar between Amsterdam and Bill's Irish henchman, Amsterdam is in four consecutive shots from two angles bent over in pain, leaning back, doubled over again, and leaning back again as Bill approaches him.
Continuity mistake: The scene during the riot where Bill and Amsterdam are fighting in the smoke, Bill takes what looks like shrapnel to the side of his stomach, but when Bill and Amsterdam face off (standing on their knees) just before Amsterdam stabs Bill, you can see Bill's vest has no cuts or blood from the shrapnel he just pulled out of his gut (and it looks like he is wearing a new vest).
