Take it to the Triarii!

[Duke Speedy of Leighton]

Very, very, very, VERY (as if in 'already ordered the first pack') tempted by Republican Roman (proper Republican, not post Marian reforms); but, it there is one period where there no contemporary illustrations for (apart from one carving on the tomb of Ahenobarbrus), what colours should I (MA in Roman Military History), paint their shields (how many brackets can you get away with(honestly))?

Present favourites:
Velites -White
Hastatii- Green
Principes - Traditional Roman red
Triarii - dark blue.

Should I add designs, post Marian was often animals associated with Patrons/Jupiter's thunder & wings etc?
What do we think gents?

[Ithoriel]

I think the answer is that you can pretty much decide yourself, since currently no one can prove you wrong.

Dark red paint is among the cheapest that you can make and can be done from readily made ingredients. Mixed from blood, iron oxide, linseed oil, etc it is both a striking colour and a useful wood protective/preservative. I'd expect that to be a possibility.

It seems that legions could be distinguished by their shields which suggests consistent colour or pattern (or both).

According to Vegetius, the Ancient Legion prevented soldiers losing contact with their comrades in the confusion of battle by painting different signs for different cohorts on their shields and they still do this" (Sed ne milites aliquando in tumultu proelii a suis contubernalibus aberrarent, diuersis cohortibus diuersa in scutis signa pingebant, ut ipsi nominant, digmata, sicut etiam nunc moris est fieri) – which might be a different colur/ pattern for each cohort, rather than something at legion level. Of course Vegetius is writing long after and may be talking through his hat!

Personally I'd have a good rummage online and pick something(s) I liked.