The purpose of the Late Roman Draco standard.

[ValentinianVictrix]

I've been scouring various ancient Late Roman works for information on standards associated with commanders. Its very interesting to note that the enemies of the Romans did not appear to have known when they were engaging the Emperor/Army commander in direct combat. Examples of this would be where Julian rallied the right wing at Strasburg, no Allemanni appeared to have recognised him so that he became a target for attack. Similarly, the Goth's at Adrianopolis did not know they were attacking Valens in person when he joined the Lanciarii and Mattarii Legions, or, if the legend is correct, that he was holed up in a farmhouse that was subsequently burned down. It also appears that neither Julian or Valens, nor Valentinian I who was almost killed in an ambush, were distinquishable from their men by wearing armour or clothing or their standards were different so that it singled them out as special target.

So, in relation to this thread I'm coming to the view that the Draco standards purpose was to denote the position of a units commander. It was probaly used as a rallying point and where those seeking orders could move to. I also believe all such standards were of a uniform colour, probably as a deliberate ploy so as not to reveal exactly where the overall commanders position was within the army.