Working on an triumvirate impression

[Theodosius the Great]

Ah! My mistake. You're right about both tombstones, Matt.
(Spank me :oops: :lol: )

The other tombstone is actually this one belonging to Caius Castricius Victor : http://www.romanarmy.com/cms/component/ ... Itemid,94/

But neither one, as you said, resembles the old Republican scuta.
So, the only evidence seems to point to Praetorians.

Right, I realize that. But weren't those early praetorian guards simply drawn from the ranks of the legionaries? Why would they have different equipment?

Yes, AFAIK, Republican Praetorians were drawn from the ranks. Author Boris Rankov says that according to Appian, Octavian and Antony divided 8,000 veterans between them and formed them into cohorts. The latter took three cohorts to the East and issued a coin honoring his own Praetorians. Later at Actium, five of Octavian's cohorts fought against Antony. (Who knows if these five cohorts were equipped differently for naval combat ?)

Same with Augustus' cohorts--no real reason for them to look "archaic". Unless, of course, their gear wasn't considered archaic at all!

We know that Augustus' Praetorians, at least the three cohorts stationed in Rome, did not usually wear their armor. Presumably, their armor just sat in storage for years until they were taken out and worn on special occassions. So, their equipment did not suffer the wear and tear of their legionary counterparts'. I see no reason to suppose that equipment in good working order, no matter how old, was thought to need any "upgrades" or "modernization". Now I may be ascribing modern thinking to ancient practices ... :|

Possibly no Mainz swirds were found, because the Romans won?

No Roman swords, period. Mainz or otherwise. But yes, I'd say that's the likeliest explanation.
The idea of a Caesarian Legionary carrying a Mainz isn't an outrageous assumption, IMO. But it does seem to be just that - an assumption.

~Theo