The tunica (tunic) was the fundamental item of clothing throughout the history of ancient Rome. It was worn by all classes, including high ranking nobility, the equestrian order, plebeians, military, slaves, men and women alike.
Clearly not all tunics were the same, and given the great importance which the Romans gave to clear social structure (note that this didn’t mean that roman society didn’t allow mechanisms for movement between social classes) the tunics they wore had differences:
The tunica of the Patrician order had two purple stripes down them (“laticlavus”), those of the equestrian order had a single purple stripe. They were generally of higher quality, and whiter than those of the poorer classes. Of course you could also have it dyed a different color to white: a range of different colours could be achieved, ranging from natural grey-ochre through to a range of colours, usually of natural origin.
The tunica of common men was simpler, also woollen or perhaps linen, less white than that of the rich and certainly of coarser material. If you don’t like itchy woollen jumpers this wouldn’t have been your favourite!
Given their essential function of keeping you warm more than one tunic might be worn on top of each other. Their length could vary, eg down to the waist, thighs or below the knees and they might or might not be tied round the waist depending on how comfortable you might want to feel. Eg at home, lounging about, you might wear it rather like a dressing gown.
Clearly an upper class Roman, when in public, would have worn a very white tunic of fine material under the traditional toga. A Roman legionary would wear it under his armour. A farmer or slave working in the fields would have worn it alone, perhaps with a belt.
Whilst various sources suggest the tunica might vary in colour and pattern (ie that it wasn’t always white) there isn’t any evidence of a rule as to it’s colouring or patterns (except the purple stripes pertaining to your rank in public).
For example, a simple yellow dye for wool can be obtained by boiling the wool together with nettle plant roots and salt. So you might ask your farmer wife to boil it and voila, a yellow tunic, but would a soldier wearing such a tunic under his armour have suffered any penalty? Probably not but the colour itself might have brought you some social stigma: there is some evidence of red, blue and green tunics being worn at times by the military (but I haven’t found yellow).
Construction of the Roman Tunic
The tunica was a single piece of woollen cloth made somewhat like a South American “Poncho”: a long strip of woollen material with a hole cut in the middle for the head. Or, rather than cutting a hole you might simply stitch two large rectangular pieces together whilst leaving an unstitched length in the middle for the head to fit through.
The two resulting flaps would fall round the front and back of the body and tied together with a rope, belt or strap. You could go further than the Poncho style and actually stitch the sides of your rectangles, minding to leave holes for where the arms were to fit through. Later evolution of the tunic also included the addition of sleeves, both short or long.
Higher class tunics were evidently made with greater care and effort and would therefore be made as a single piece, rather like t-shirts are today. At the opposite end of the scale, the satirist Juvenal tells us of a “tunica molesta” used as part of torture: a rough tunic which could be soaked with flammable substances….
Juvenal in his Satire #8 tells us how a gladiator fought and dishonourably fled across the arena so as to not be caught, yet everyone knew who he was because of his highly distinguishable golden tunic.