00:08:25 - 00:12:30 - A bloody battle that ends when DDL kills Liam Neeson. Lots of dudes with blood all over their clothes standing around but just talking, but if that's too much skip to 00:13:40 Here's Wikipedia's recap: "In 1846, in Lower Manhattan's Five Points, a territorial war between the "Natives" (those born in the United States) and recently arrived Irish Catholic immigrants, is coming to a head in Paradise Square. The Natives are led by "Bill the Butcher" Cutting (Day-Lewis), a Protestant nativist. The leader of the Irish gang, the Dead Rabbits, is known as "Priest" Vallon (Liam Neeson). The gangs meet in a bloody battle, concluding when Bill kills Vallon, which Vallon's son Amsterdam (Cian McCormack) witnesses. Cutting declares the Dead Rabbits outlawed and orders Vallon's body be buried with honor. Amsterdam seizes the knife used to kill his father, races off, and buries it. He is found and taken to the orphanage at Hellgate."
00:23:00 - Nobody gets hurt here
00:42:30 - Just some punching, nobody gets hurt here
00:50:00 - Nobody gets hurt here
01:01:20 - Some people get hanged here, but it's only seen from a distance for a second, then it's just shots of the audience reacting to it
01:10:30 - 01:11:40 - There's some bareknuckle boxing here, some blood, not too bad I don't think though, nobody gets killed
01:16:45 - DDL gets shot, but LDC saves him so it's only a glancing shot, there's a struggle ant at 01:17:10 the assailant gets shot during the struggle. DDL then threatens him with a knife but the assailant dies before DDL can do anything to him. You can probably watch all of this with no issues
01:20:00 - Nobody gets hurt here
01:25:10 - End of part 1
00:11:00 - Nobody gets hurt here
00:19:40 - LDC tries to throw a knife and then pulls a gun on DDL, but DDL knocks the flying knife aside with his own and then throws a knife into LDC's belly before LDC can get a shot off
00:20:25 - DDL takes his knife out of LDC's belly, then smacks him across the face with it (flat side, like a slap, not a slash)
00:20:50 - You'll probably have trouble with this scene, DDL crawls on top of LDC and head butts him in the face a bunch of times, then decides not to cut him or kill him but instead brands his face with a hot knife, marking him. This goes until 00:22:20. You could probably listen to it OK, but I would guess seeing the threat of violence might be too much for you
00:33:00 - There's a bit of a struggle here but you don't really see anything
00:37:20 - LDC finds Henry Thomas hanging on a fence, stabbed through with one of the posts. HT tells him it hurts too much and for LDC to just kill him, so LDC shoots him in the head. Just skip this and go to 00:38:40
00:49:05 - DDL throws a butcher's knife and hits the new sheriff in the back with it. Then at 00:49:40 he brains him with his club, which you don't see, but you hear
00:54:45 - Some riot/looting violence but I didn't see anyone get hurt (some guy ends up standing there with blood all over him though, but no idea what happened to him)
00:59:30 - Just skip the next 3 minutes, it's all kinds of riots/looting violence, some is pretty bad, just know the whole city is rioting and the army/police have been called out to quell the mob.
01:03:40 - Just skip the next 6 minutes as it's all a big bloody, violent finale. Here's what the Wikipedia plot recap about this part says: "The New York City draft riots break out, and many upper-class citizens and African-Americans are attacked by the rioters. Union soldiers enter the city to put down the riots. As the gangs meet, they are hit by shells from naval ships in the harbor firing directly into Paradise Square. Many are killed, and an enormous cloud of dust and debris covers the area. Union soldiers then fire into the square, killing numerous people, including McGloin. Amsterdam and Bill exchange blows in the haze, then are thrown to the ground by another shell blast. When the smoke clears, Bill discovers he has been hit by a piece of shrapnel. He declares, "Thank God, I die a true American." Amsterdam stabs him, and Bill dies with his hand locked in Amsterdam's."
You can watch the rest from here on out.