Rome and it's legions are usually associated with the color crimson. And historically this seems to be consistent, except with Pompey who used blue. Was their a significant reason, organizationally or symbolically?
He did? What's the text to support that claim.
Also, in general, the aesthetic of Roman legions you are used to is largely the product of Hollywood. For instance, this is a fresco that depicts a soldier from Pompeii. It's not the best preserved, but I think you would be hard put to claim it's red. This one has a little more detail.
I have no idea why Hollywood decided Roman soldiers wore red. I've heard they made their soldiers wear bracers to cover tan lines from watches.