Continuity mistake: When Corporal Allen pulls Private Hitch off the ramparts when Hitch is shooting at Zulu's in the hills with his pith helmet on backwards, Hitch gets shot in the leg, and Allen pulls him in. Allen is shot in the chest, he clutches his chest, falls inside ramparts with blood underneath his clutching hand. When you see him after camera cut he is clutching the OTHER side of his chest.
Plot hole: There must have been a shortage of Martini-Henry rifles for this production, for in the climactic charge scenes in which the three ranks of British soldiers deliver volley after volley into the Zulu masses, the soldiers closest to the camera are equipped with lever action Martini-Henry's but those further back in the line can be seen pulling up and back on bolt action rifles.
Continuity mistake: After the Zulus' final charge which follows the rendition of "Men of Harlech", they appear on the hills round Rorke's Drift to give their salute to the garrison before leaving. In one shot, filmed from behind the Zulus, both buildings, church and hospital are standing even though the hospital burned down during the battle. Seconds later in the next shot of the post from the hills, only the church is standing and a column of smoke rises from the ruins of the hospital. I believe that some scenes were filmed of the Zulu Impi crossing the Buffalo River and marching to Rorke's Drift, but were cut from the film. The first shot mentioned above could be one of these.
Deliberate mistake: This is a mistake which is a function of the limitation of the special effects at the time and what the censors would allow in the cinema but the wounds suffered by the Zulus do no justice to the horrific injuries that the Martini Henry rifle would have caused. The Martini Henry fired a big .45 inch soft nosed bullet that usually shattered on impact. It would have caused massive gaping wounds rather than the little red dots and trickles of blood shown on the Zulus and left many of them limbless as the bullets tore off arms and legs.
Factual error: After the battle, the remaining Zulus left the field without making a sound, unlike the movie.
Factual error: In the actual battle the wagons were not tipped over, the space beneath was filled with mealie bags and ammunition boxes. This made the bayonet equipped rifles more effective against the much shorter assagais, since the assagai-armed Zulus could not engage without climbing onto the wagons.
Factual error: In history, the battle at Rourke's Drift was NOT ordered by Cetewayo. Cetewayo gave specific commands to his men not to attack any entrenched British positions; the Rourke's Drift assault was in fact spearheaded by one of his headstrong siblings eager to prove his warrior worth to his brother.