Factual error: When the Romans fight in Germania, the forest is made up largely of European black pines (Pinus nigra). However the woods there and then should have been mostly beeches (Fagus sylvatica). (00:02:30)
Continuity mistake: At the beginning when Maximus is walking past the rows of soldiers look closely and you can see some of the same soldiers twice. (00:03:15)
Continuity mistake: Watch as the Germanian leader gets killed. A soldier charges and stabs him on his left side. When it cuts the soldier charges and stabs him again. (00:03:35)
Continuity mistake: At the very start of the film when we see Maximus for the first time, he is talking to his friend Quintus. Two boys run past, yet when it cuts to another shot they have vanished. We should have been able to see them at least running off in the background somewhere. (00:03:40)
Continuity mistake: In the beginning when Maximus says "Lean and hungry. Still nothing?" in which he gets the answer "Not a sign" from Quintus. Watch the soldier behind them handling the catapult. When it cuts that soldier is suddenly gone. (00:03:45)
Continuity mistake: When Quintus tells the soldier to move the catapult he is standing right behind Maximus. When it cuts, he is further away from Maximus. (00:03:50)
Character mistake: Prior to the opening battle, Quintus says "The danger to the calvary" instead of "cavalry." (00:04:00)
Continuity mistake: Before they attack the Germanians, Maximus says "Strength and honor" to Quintus and he replies. Then Quintus says the same to another soldier who is facing him. When it cuts the soldier is suddenly walking away. (00:05:10)
Continuity mistake: When Maximus says "On my signal, unleash hell" he takes off with his horse. Then he rides through a stand with soldiers and the soldiers gets up on their feet. Then it cuts to a close-up of Maximus riding and as the camera zooms out the soldiers gets on their feet again. (00:05:30)
Continuity mistake: Right before the attack on the Germanians when Maximus gets to his soldiers and shouts "Fratres.", you can see two soldiers walking right behind him. When it cuts to the soldiers shouting "Maximus.", the two soldiers behind him has suddenly disappeared. (00:06:15)
Continuity mistake: Just before the battle with against the Germanians begins, while the Germanians are taunting the Romans, there are many arrows in the trees and in the ground. Twice we see this. Problem is that the disciplined Romans had not fired a single arrow at that point and no skirmishers, which could have been authorized to shoot before the order to "loose" can be seen in the open area in front of the defensive position. (00:06:50)
Continuity mistake: When the Roman soldier shoots the signal arrow before the attack against the Germanians, you can see his bow twist at least 45 degrees between the shots. (00:07:25)
Revealing mistake: In the beginning of the film at the major fight sequence. When you see the Romans shield themselves with the rectangular shields against the barbarian's arrows and then they charge at each other. If you look closely enough, you can see two Roman soldiers standing there having a great laugh, one pointing a sword smiling, and the other one staring at the ground laughing to his heart's delight. (00:09:15)
Factual error: The opening battle is wildly inaccurate. The Roman legions were trained to fight as a regimented force, and to maintain formation for mutual support. In the film, the formation collapses instantly upon contact with the enemy. Further, the Roman legions used spears called pila. Doctrine called for them to be thrown while the enemy closed. The Romans would then draw their swords and fight, while remaining in formation. Though the Romans are shown holding their pila in the opening scenes, they are never used against the barbarians, and we see no pila-riddled shields and/or corpses in the background. (00:09:15)
Continuity mistake: At one point during the first Germanian attack you see the Roman soldiers creating a line-up with shields, soon after followed by the Germanians running towards them off-hill (starting their attack). Clearly a few Germanian stopped fighting a little too early and you see them (left-side) turning and looking around. (00:09:15)
Revealing mistake: When Maximus is riding against the Germanians, as he meets the first Germanian, he hits the Germanian's spear and hits him with his sword. However, the hit isn't even close, but about 30 centimeters from the Germanian. This is even seen without slow motion. (00:09:30)
Revealing mistake: When Maximus charges his cavalry against the Germanians in the first battle, he decapitates a Germanian standing in front of a tree. In the side-on shot of this, the Germanian is obviously a mannequin, as when the head comes off, so does the wig on top of it. (00:09:40)
Continuity mistake: When Maximus chops the head off the German at the beginning of the movie, his sword is supposed to be stuck to the tree. However after he has chopped the head off you can for a second see the sword in his hand before we get to the shot where the sword is stuck to the tree. (00:09:40)
Revealing mistake: In the beginning during the war with the Germanians when Maximus falls off his horse you can see that it's not Russell Crowe but a stunt double. (00:09:55)
Visible crew/equipment: During the Germanian battle, when Maximus falls off his horse you can see the ramp, on which the fake horse (yes it's fake, as shown in Special Features in the Extended 3 Disc Edition), is being pushed forward on and finally ejected off. (00:10:00)
Chosen answer: Because they would be the ranking soldiers, and accustomed to being given orders. Being disciplined, they would obey Quintus without question. The legions would necessarily have soldiers assigned to following orders at different times, similar to how a captain would give an order to a full room, and the first mate would be the one to carry out the order.
rswarrior