Hot damn! I'm excited. A Roman question that my knowledge set should be fit to answer!

As to why you think Ancient Romans were wearing so little, what they were actually wearing was made of boiled wool that went through a process (that a quick online search suggested was called fulling which apparently involved a lot of urine in the first part of the process-so much so that it was taxed according to wikpedia). This wool was high quality and would keep the wearer warm in cold weather.

Wool would have done decent at resisting heat. There is a great BBC special about Pompeii where they investigate how the inhabitants actually died. Without going too much into that issue-they flash cook a piece of meat covered in boiled wool much like the Romans would have used. The results of the experiment showed that the pork meat cooked to a medium level and while the boiled wool singed it didn't burn as much as you think it would given 300 degrees C of heat for a spurt of time.

[paragraph about connection between Romans and modern wool clothing edited out]

Medieval Italians were in large part, cultural and (to a smaller degree) genetic descendants of various european peoples who migrated into Rome, not just Romans themselves. The "fashion" among the "barbarians", for example germanic tribes, was different than among Romans. Germanic peoples between the dawn of the Iron Age, and almost up to 17th century wore quite similar outfits, which usually was a long sleeved tunic + long pants for men, and a long sleeved, ankle length dress + apron + headscarf for women. This type of fashion was remarkably stable throughout the centuries, and in almost all Eurasia, from Mongolia to Ireland, and from Finland to southern Balkans and Turkey.

There are several reasons why this was the case. First of all, the typical elements of Iron Age/Medieval clothing are designed to use the cloth as effectively as possible. Combined with the fact that most pre-Rennessiance people would only own a few sets of clothing, every item was designed to be as useful in as many types of weather as possible.

This is why, for example, medieval art depicting men at work shows them in long tunics with sleeves rolled up and the rim of the tunic tucked up behind the belt, or sometimes pants-less, with the long tunic doubling as a "skirt" below the belt. Those men simply did not have a "summer tunic" with short sleeves or hip length front, as this would be unnecessary and wasteful. Instead, the tunic was an "all purpose" item for all weather and all kinds of work.

As for long pants, those were a cultural mark of "barbarians". The use of pants was ridiculed by the ancient Greeks and Romans.(see: Euripides, Cyclops, 182, Aristophanes, Wasps, 1087). Romans themselves slowly adopted pants in the military, in the form of braccaea and femoralia (sometimes nicknamed "feminalia") - that is, short pants copied from the Celts. Both were considered "unmanly, feminine" but necessary part of military equipment for warmth and comfort. Slowly, the pants were adapted by civilian Romans, and in the Middle Ages, Italian Romans would wear both regular trousers (rarely) or various shortpants/briefs coupled with long stockings. The type of leg covering depended on the length of the "skirt" of the tunic.

The adoption of leather shoes instead of sandals, is, quite curiously, tied to the technology of writing. In 7th century, Europe had been cut from the supply of Egiptian papyrus, and had to switch to parchment instead. Since parchment is made of soft, scrapped leather, this meant that animal husbandry, production of leather and and tanning went into a frenzied overdrive, and every scrap that was to thick and small for a page of parchment was sold to leatherworkers and shoemakers instead. For the first few decades, leather become extremely expensive (since Frankish court and papal cancellaries bought leather and parchment wholesale and had dibs on it), and then significantly dropped in prices, when demand subsided. This means, that by the end of 7th century, it suddenly become possible for an average person to buy leather shoes/boots. Shortly after, well made leather shoes become a fashion statement, and all the rage across fashion-concious medieval cities. Sandals become a legwear for poor peasants, and humble ascetic monks instead, because everybody who was somebody wanted leather shoes.

So, in short, the greatest influence on the change in Roman clothing was not weather, but fashion, and invasive cultural traditions.

other sources:

Collis, J. The Celts: Origins, Myths, Inventions

C. de Hamel, Scribes and Illuminators

Payne, B. History of Costume Lever, J. Costume and Fashion: A Concise History

IIRC, togas were formal attire, not day to day wear, for most of Roman history? Anyone know if this is true?

Edit: this is a related question not speculation

If you have a follow-up question to the original question, please feel free to ask it. If you have heard or read something which might be related to the question, and you want to check it, then make sure you ask it as a question. Do not post "I'm not sure if this is true..." or "Someone will correct me if I'm wrong." If you're not actually answering the question, then make sure your comment looks like a question.

I don't think your selection of paintings is representative. The first picture shows Venice, which is more than 400km north of Rome, and on another sea.
The second picture was painted in Flanders for the Dutch bourgeoisie. Not sure what makes you think the painter shows Italy. Objects in the room are typical Dutch for the time (the glasses), the architecture pictured in the mirror looks quite Dutch - and one would also more likely see a gold trader in a northern area.
I don't know about the historical accuracy of the last one either.

None of the costumes are every-day attire. They're supposed to communicate status or occasion. Such costumes are then not made for comfort - often the opposite.

Hi! Great question!

So, I'm not an expert on Roman dress, and besides that's already been beautifully addressed by /u/texinchina, but I am pretty familiar with 14th through 18th century Italian dress, both as an area of study and in practical terms (I do reenactment and portray a mid-16th century Venetian courtesan).

I think the biggest issue to consider is climate change. As another commenter mentioned, the Roman warm period ended in the early middle ages and that began a gradual shift towards what is commonly known as the "Little Ice Age" which persisted in Europe until the 17th century or thereabouts. I've seen temperature estimated at 1-3 degrees Celsius cooler on average during this period than it is today, and while that wouldn't mean that, say, Venice didn't experience extreme heat in the middle of July, it would mean an overall difference that could account for why heavier clothing became the norm during this period, when compared with Roman clothing.

I think the other thing to consider is that what we know of the clothing medieval Italians wore is based on the upper classes in large part. The representations we find in the written and visual record are almost always of the elite classes, and really only towards the end of the 15th century do we start to see an interest in painting "pastoral" scenes of peasants (which were highly idealized).

With that in mind, it's important to put this in context. An elite person would not be outside where it was hot. They would spend large parts of their waking lives indoors, where it was cooler, enabling them to wear layers of heavy clothing without suffering.

Also consider that formal portraits present a somewhat skewed version of what an elite person wore. There's been some great scholarship done in recent years on the wardrobe of Eleanora di Toledo, Duchess of Florence during the mid-16th century, and what's emerged is information that supports the theory that the big heavy gowns we see in portraits either were only worn for state occasions, or didn't even exist in reality. What Eleanora wore when she was in informal settings tended to be much less than what she wore when she sat for Bronzino's famous portraits of her. We know that she was constantly pregnant and, after her last pregnancy, constantly ill, and written descriptions of her during this period of her life suggest she tended to favor a garment called a "zimarra", which was essentially a caftan. We also know based on the analysis of her wardrobe accounts that she ordered zimmare in much larger quantities than pretty much any other type of garment.

Another type of garment that was popular for informal settings was a type of gown called a sottana. In its formal applications, it was worn under zimarre or another type of fitted gown called a veste, but informally it was worn on its own. It had a low neckline which exposed the top of the bosom and usually had detachable sleeves. Now, there's no solid* evidence in the written/visual record that elite women went about wearing their sottanas without sleeves during heat waves, but I can tell you from personal experience that the sottana is pretty comfortable in hot weather (I live in a part of California that averages 90+ degrees Fahrenheit in the summer) when you remove the sleeves.

Finally, we are super fortunate that a handful of these sottane still exist and have recently undergone significant study and conservation. The most famous, other than Eleanora's burial gown which was studied by Janet Arnold in the early 1980s, is the so-called Pisa Gown, which was discovered in a church in Pisa several years ago, adorning a statue of the Virgin Mary. Matching the description of this gown to one in Eleanora's wardrobe accounts, it's reasonable to presume this gown belonged to her or one of her ladies-in-waiting and was donated to the church. I haven't had the privilege of studying this gown in person, sadly, but I can say that it fits the historical record very well. It's undergone some conservation (apparently, the back was cut away to put it on the statue) but it's still largely in its original form. This is a huge deal, since nearly complete costume of this period that hasn't been mouldering in a grave for hundreds of years is very, very rare.

If you're curious about learning more about Eleanora's wardrobes and where I pulled my info from, check out Moda a Firenze, 1540-1560 by Landini & Niccoli. The text is in both English and Italian, and the English translation is generally pretty solid.

*What we do have are some frescos that show women wearing sottane without sleeves in Venice, but it's always a question as to whether or not those women are intended to portray courtesans, who are a whole different ball of wax in terms of clothing history.

I had understood there was a period of notably warmer weather during a significant part of the Roman era, but I read it such a long time ago, I cannot recall whether it was a reliable reference. Anyone?

for orgies and shit