Factual error: King John succeeded in capturing Rochester Castle. The French arrived in England about six months later.
Factual error: William d'Aubigny was not killed during the siege. He survived to support John's son, Henry III.
Factual error: Rochester Castle is seen standing alone and isolated from any other settlement. In actual fact it stands on the edge of the City of Rochester and very close to Rochester Cathedral, both of which certainly existed at this time.