Face mask or face guard in late roman period

[Robert Vermaat]

The lost column of Arcadius depicted a few helmets with masks and crests.

Yes, but also with some other 'fanciful' weapons such as double-headed axes, 'Phrygiasn caps' (the defeated enemy is supposed to be a Gothic army in Roman service) as well as 'Thracian' shields, neither which you would expect to see in a Late Roman inventory. It's clear that the enemy is supposed to be 'Eastern'. And while I count 5 'facemask' helmets, some of them complete with a neck (??), there is no 'common' ridge helemt shown. Which is odd, because other details seem quite correct (some shields, cloaks) for the early 5th century.
Apart from the obvious problem that this is a very late copy of a now lost original (which will keep us guessing forever), I think that many 'classical' pieces of arms & armour made it to this monument, some doubtless taken from older monumnets and some even purely symbolic, which leaves me at leasy in doubt about the credibility of the 'facemask' helmets shown, and still unprepaired to accept this as proof for their existence in the Late Roman inventory. Just my opinion.