Factual error: 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 correctly equipped with lever action Martini-Henry rifles but those further back in the line can be seen pulling up and back on bolt action rifles, wrong for the era.
Factual error: The narrator mentions that the Cheyenne tribe split in half in northern Nebraska. The scenery would suggest otherwise, as there are no mountains that high in Nebraska.
Factual error: In reality, Commodus did not die in the arena - he was strangled in his apartments in 192 A.D. by an athlete who was hired by a group of Senators conspiring against him.
Factual error: At the start of the excommunication scene, the monks are chanting Dies Irae, a thirteenth century Catholic poem, but St. Thomas Becket died in 1170, almost a century before the poem was written.