Other mistake: The giant medallions that Pilate takes from a chest and then places on the pillar of the Temple do not bear close inspection as images of Tiberius, for some reason the name Augustus is lettered along with abbreviations not easily discerned as what was then used. The image behind Pilate when he is in court is similarly inauthentic but I would think that no-one but an exacting numismatist would even notice this if it is indeed such a major mistake.
King of Kings (1961)
1 other mistake - chronological order
Directed by: Nicholas Ray
Starring: Jeffrey Hunter, Hurd Hatfield, Ron Randell, Siobhan McKenna
Revealing mistake: Have a look at some of the beards (and wigs) in this movie, the facial hair is coming loose on several of the disciples' beards.
More quotes from King of Kings
Trivia: Jeffrey Hunter, the actor playing Jesus, had his chest and armpits shaved for the part (why is anyone's guess). He was also barred from giving interviews.
Question: The first disciples to follow Jesus are shown as John and Andrew. But where did James brother of John vanish and there is no record in the Bible that these two followed the Baptist. Surely Philip and Bartholomew also are involved at this point or shouldn't the whole scene have started with Peter and then moved back to Andrew and the two boys of Zebedee? The assembling of the Apostles doesn't follow biblical accounts at all and a juvenile John is very much set apart from any brother.