Just a follow up and some added resources regarding this question.
Dr. Helen Nicholson is a reader in History at Cardiff University. She specialises in the Military Orders and in the Crusades and has written many books and other publications about those subjects..
From a letter from her addressing this very question.
"This is a good question. I agree with you: I think that, like the Templars, the Hospitallers would have borne the same arms on their shield as on their banner. David Nicolle has also assumed this, in his Osprey book on the Knights Hospitaller, 1306-1565. The earliest pictures of Hospitaller shields that I have found are from Caoursin's account of the siege of Rhodes in 1480 -- these do show a red field with a white cross. This is not absolutely conclusive, but it does seem most likely that the Hospitallers' shield had not changed, and had always been red with a white cross.
Alas, I do not know of any Hospitaller frescoes like those at S. Bevignate in Perugia. Matthew Paris's _Historia Anglorum_ has one image of the Hospitallers' banner thrown down in defeat in 1239: this shows a red field with a white cross (London: British Library, MS Royal 14 C vii, fol. 130v). Again, in one manuscript of his _Chronica Majora_, Matthew showed the banners of the Hospitallers, the Templars and the king of France: and again the Hospitallers' banner has a red field with a red cross (Cambridge: Corpus Christi College, Parker Library, MS 16 fol. 141). He never shows the Hospitallers' shields. I think that it would be most likely, however, that the Hospitallers' shields matched their banner.
I hope that this is some help.
Yours sincerely
H. J. Nicholson "
A follow up e-mail to the requestor from Dr. Nicholson
Caoursin's illuminated account of the 1480 siege of Rhodes survives only in manuscript, so far as I know: Paris, Bibliothèque nationale, MS Lat. 6067. I am not aware of any modern facsimile editions. There are 15th and 16th-century printed editions, but they are illustrated only with black-and-white woodcuts.
Individual illuminations from the manuscript have been reproduced in various places. Fols 40v and 175v, which show the shields, are reproduced in Elias Kollias, _The Knights of Rhodes: The Palace and the City_ (Athens: Ekdotike Athenon S.A., 1991), ISBN 960-213-242-6, pp. 50, 53.
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Reproductions of both Matthew Paris's drawings of the Hospitallers' banner appear in my _The Knights Templar: A New History_ (2001), pp. 64, 166.
Yours sincerely
H.J. Nicholson
In addition David Nicolle is a British historian specialising in the medieval military history. He is a prolific author, contributing to many of the Osprey books including two about the Knights Hospitaller.
In a letter to the same requestor regarding the same question.
"I have been putting a lot of thought into this and have realised that there is
very little evidence one way or the other. So I have summarized my opinions as
follows:
I am sure that in the early decades all brethren, knights or sergeants, carried
black shields with white crosses, but the size, position and perhaps even the
shape of the cross could vary.
There was probably a short period when black shields with white crosses, and red
shields with white crosses, were both being used. But after that the shields
would almost always have been red - though perhaps not always so.
I do not think that brother-knights would ever have had their own family
coats-of-arms on their shields, though there was later some quartering of the
arms of the most senior men with those of the Order - probably only in things
like manuscripts and carvings rather than on military equipment.
Knights who were temporarily associated with, or were attached to, the
Hospitallers did continue to use their own coats-of-arms.
This is all rather imprecise, but I hope it helps.
Best wishes, David "
Personally, I like to have my facts straight regarding history and don't like to use artistic license to fill in gaps. Its why history gets distorted so easily when people use the excuse of "we weren't there so we won't know so I'll just make **** up" because in individual assumption it makes sense. I'm all about painting figures the way you want and what makes you happy. But if its a question regarding historical accuracy or the question is on the table regarding what is historically correct, then its owed to the asker to provide the most comprehensive information possible or that we know. Not quote partial fact, make your own assumption and defend that position as the only answer and then hide behind the artistic license argument, thats hypocritical.
So Marc, as you say :" As the colors where red with white cross became standard after 1248 it is obviously that the banner is wrong with the black dress and white cross because it was more then 100 years after the order was rised.
Nevertheless: as always we where not there, and it could be happend.
That's the freedom of the artist. which is it, obviously? or artistic license? If its the former, I'd be curious to see where your documentation comes from and how you made that assumption. If its artistic license, why bother making the comment that you think the flag is wrong in relation to the surcoat?
