The M1A1 Thompson has 20 rounds in-game, despite the in-game model having a 30 round magazine.
When the storyline is completed, the end information states that 60 million people died during WWII, when the actual number of deaths is about 72 million.
The PTRS-41 is regarded as a sniper rifle in Call of Duty: World at War but in real life, the PTRS-41 is actually an anti-tank rifle firing a 12.7x108mm armor piercing round.
Although this is one of the only video games to reenact the Battle of Peleliu, there were many historical errors. Sullivan says at the beginning of the battle that the fighting was going to be three days when it was expected to be four. Of course the battle lasted two months.
Also the LVT you are on is too small and too fast to be the ones used in World War II. The carrier that launched it was also way too close to the beach as it was way further out in the actual landing. The coral you get stuck on actually could not stop an LVT, and could easily be rolled over.
The terrain on Peleliu in the game looks like it is a jungle island when it was a island mostly with coral terrain and sand.
Throughout the levels you are on Peleliu you encounter many Japanese banzai charges, but there were almost no banzai charges during the actual battle. Also the Japanese were mostly fighting in underground bunkers and not out in the open as depicted in the game.
In the game you take the airfield on the same day as the landing, but it was not captured until the next day. There was also no counter-attack to retake the airfield as depicted in the game.
The PTRS-41 is listed under bolt action rifles when it is a gas operated anti-tank rifle.
The M1 Carbine is incorrectly called the "M1A1 Carbine" in-game even though it doesn't have a folding stock.
When the time comes to choose to save either Roebuck or Polonsky, no matter who is killed, the dog tags Miller receives at the end of the battle bear Roebuck's name.
When Reznov and Dimitri get ambushed by a sniper in "Vendetta", you can see that there is nothing is shooting at you and Reznov. The sniper shots are just bullet impact particle effects spawning at scripted events. The sniper will only spawn if you follow Sgt. Reznov into the building he crashes through by window.
In the zombies map Nacht Der Untoten, the Thompson incorrectly costs 1500 points when it actually cost 1200 points. This has been fixed in the Call of Duty: Black Ops (2010) version.
The first Russian mission is set in 1941 however the wrecked tank in the street is a TigerII or King Tiger which did not enter service until 1944.
At the roof of the Reichstag, the version of the Soviet national anthem playing is the post-1977 version.
For some reason there are pieces of American equipment such as Bazookas scattered inland on Pelileu even before the Americans make it that far inland.