I said it was a French Crusaders cross, because it was being used by the French monarchy at the time. Troops working directly for the French crown, who did not have a coat of arms of their own, used that color of surcoat. Likewise the English one was the coat of arms used by several British monarchs at the time, in one variation or another (Richard I used the white cross on red background, usually with a British lion center). The black and white was a pattern used by a number of Holy Roman Emperors of the time, again in one variation or another. And while they were not necessarily uniform, knights whose loyalty was to one of these monarchies would very commonly adapt their personal coat of arms to reflect the pattern commonly used by their lord. This was particularly common among non-nobility knighted in response to accomplishments, who did not have a family coat of arms and so would need to adopt one (and the Crusades produced quite a few such individuals... either because there were opportunities to distinguish oneself, or just because they got a field promotion because all the noble-born knights got killed).
So while it was not a national uniform, it was a symbol of loyalty to a particular monarchy ... and as such, a recurring theme among the coats of arms used by their knights. Nobody just sat down and assigned colors to particular countries ... it just so happened that monarchs of England, France, and the H.R.E. (Germany) were all using various colors of cross patterns at the time. Their choice of cross patterns was probably done deliberately as a symbol of support for the Crusades - hence the term "Crusader's Cross" being applied to those coats of arms. The same basic cross pattern (large cross in center) also appears on the various Kingdom of Jerusalem coats of arms, and those of some - but not all - of their various secondary entities (notably Ibelin and Tripoli). And while the exact pattern changed depending on who was in charge at the time, they tended to keep the basic look.
But thanks for making that note ... just because a particular pattern was a recurring theme in the coat of arms of knights from a particular location and loyalty, nobody should confuse it for a national or official uniform. Heraldry didn't work that way. It was, at its very base, highly individual in nature... and never really "standard" of anything. Even those who adopted the basic pattern of their superiors tended to individualize it in some way.
The "French Crusader's Cross" was just a common and popular coat of arms pattern for anybody from France going on the Crusades, or wishing to show support for them ... and was never standardized in any single form that I know of. The English "St George's Cross" would be somewhat standardized in the 100 years war, but even then was never a "uniform" of anything... but the lack of standardization certainly didn't reduce its popularity much. That was just the way heraldry worked.
I sometimes forget that not everybody realizes this ... and so tend to over-generalize. Sorry if I gave anybody the wrong idea.
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I've seen the name of that Templar flag written Baucean, Bauceans, Beaucent, and any of several other variations. They are probably just the various spellings of different languages. (I'm pretty sure "Beaucent" is French spelling, as the final "t" is more or less silent in French pronunciation... and therefore not being present in the English variation.)
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And yeah, technically a "surcoat" is worn over armor, as opposed to civilian clothing.
The 1259 changes are a little after our mod, unless somebody stays in the game for a LONG time. There are no plans to model the red, as far as I know.
And I think the page I quoted from the Primitive Rule of the Templars included the part about only knight-brothers being allowed to wear white cloaks.
But yes, those just mentioned are the basic Templar/Hospitaller uniforms currently in the mod. (The one that is NOT there are the white robes with the huge, awful-looking red crosses all over them... which I was trying to shoot down before anybody actually thought there was any history behind that.) Either solid colors, or with the smallish cross to the left side.
They were not my models - Raz had them done properly before I got involved in the mod.