William the Bastard's Papal Banner

Another one flag post for today, this time we have my version of William the Bastard, the Duke of Normandy's Papal banner. I've taken the flag from the only source the Bayeux Tapastry, The only pictures I could find online were not great, so there's a little artistic liceanse used, but so what the tapastry was made some 10 years, (approx) after the battle, and there seems to be no end of speculation as to who and where it was made.
The banner itself was carried by Eustace of Boulogne and was given to the future king of England by the pope, Alexander II to battle the so called usurper Harold Godwinson.