Factual error: The crescent as emblem on Saracen pennants is anachronistic as it appeared on Islamic military flags no sooner than the 15th century A.D.
Visible crew/equipment: When the Muslim armies approach Brendan Gleason's castle there is a side shot of the Muslims army coming to a halt. You can see the marker stake with yellow tape at the top (used during production as a mark).
When the Christians fire their first volley at the Muslims, one of the guys screams a Wilhelm as he falls.
Hospitaler: I put no stock in religion. By the word religion, I've seen the lunacy of fanatics of every denomination be called the 'will of God'. Holiness is in right action an courage on behalf of those who cannot defend themselves. And goodness - what God desires - is here and here. By what you decide to do every day, you will be a good man - or not.