The Italians knew that ancient Greek theatre (and, by extension, ancient Roman theatre) involved a chanting chorus and—occasionally—musicians. They intuited that ancient Greek and Roman drama was entirely sung, not spoken, with a band or orchestra accompanying the performance. Italian composers and theatre companies therefore resurrected this "ancient tradition" by writing and performing the first operas. But they were mistaken; Greek and Roman drama was not sung in its entirety, nor was it always accompanied by musicians. So opera, an entire genre of music and theatre, the most popular form of entertainment in upper-class Europe for about five hundred years, was created out of thin air out of a misunderstanding about ancient Roman theatre traditions.

During the Early Middle ages, Charlemagne invited a lot of scribes, learned men, etc. to his court in Aachen. There they copied down a lot of ancient Greek and Roman writings (thanks to that ~7000 works survived to this day which otherwise might have been lost to us). But thats irrelevant. The more important thing is that these scribes developed a new type of script - the Carolingian miniscule, which was much easier to read than the Roman cursive script or Roman scripts in general. It also had a few new features that other forms of writing did not have during the Early middle ages - uppercase letters, punctuation and actual spaces between words.

Now, as with many things that happen due to only one great ruler, after Charlemagne died, his heirs did not care about the developments of writting or keeping a large court of learned men in Aachen, thus they were dispersed, and with it - the Carolingian miniscule slowly faded out of existance, being replaced by the Gothic script. However, during the Renneisance, many Italian writers found these parchments with the Carolingian miniscule and though it was the Romans/Greeks that wrote like that and thus "revived" this "Greeko-Roman script".

EDIT: added a bit more info about the Carolingian miniscule and what happaned to it.

I hope you do not mind if I expand the question a bit. I admit that I do this partially because it is a story I recently learned and wish to tell, but I do think this is part of the wider idea of the Renaissance - even if we must move beyond just Italy to Germany and France.

What I want to talk about is a peculiar book that came out in 1593 - In artem analyticem Isagoge by François Viète, Seigneur de la Bigotière, former cryptographer to the King of France and France's premier mathematician. Opening the book, it is clear it is about math, and in fact if you look closely it covers what we tend to call "Algebra": solutions to equations with unknowns, relations between different ratios, formal rules of symbols. Yet of course the title includes "Analysis". Today if you were to try and divide mathematics at the highest level we would call one half "Algebra" and the other "Analysis", and if I were to try to summarize the difference I would say that Algebra tries to abstract to the highest level the structure of a set of objects, while Analysis is interested in the specific properties of objects. So to see a book that switches the two areas is very weird, like seeing someone call a dog a cat and vice versa. Certainly related, yet the exact opposite of what they are. And worse, he starts to use very strange words for things well known even at the time he published. What the hell is the Zetetic? The Poristic? The Exegetic? Why the arts of turning a problem into an equation, the use of algebraic (sorry "analytic") theorems, and the translation of "analytic" solutions to geometric problems. You never read about this in High School. So what is going on? What is Viète doing? Why?

To answer this question, we must situate ourself in the context of where math is in the 16th century in Europe, and put ourselves in the shoes of people who were dealing with the ideas of the Renaissance. So, in brief: the heart of the European mathematical tradition comes from the Greeks. You are probably familiar with names like Euclid and Pythagoras from high school, and so would Viète. This tradition was passed down to Western Europeans, with a big wrinkle: much of the mathematical texts of the Greeks stopped being copied by Europeans sometime around the 5th century. There's a huge gap in new mathematical texts that starts around then in Europe, and continues on till the 12 century. But of course there's one group of people busily copying the Greek texts and even doing new work: the Islamic world. Arab[1] scholars had begun systematically translating both Greek and Indian mathematical texts beginning in the 8th or 9th century. And in doing so they began to tackle many problems known to the Greeks involving what we tend to think of today as equations: solving linear and quadratic equations (mostly know to the Greeks), attacking cubics[2], and higher dimensional problems. In fact they did so much on this that the very word "Algebra" comes from Arabic: "al-jabr" meaning "reunion of broken parts" from Al-Khwarizmi's[3] Ilm al-jabr wa'l-mukabala. This work then gets translated into Latin beginning in Spain in the 10th century[4], and this coupled with the growth of European intellectual activity led to more and more Europeans becoming aware of "Algebra"[5].

But of course this creates a big problem for a certain type of European in this era. You see, part of the Renaissance was the rebirth of Greek in Western Europe, and as more and more European scholars became involved many of them came to a simple conclusion: All good things come from Greek, and if so, all good things should come from Math. Yet this "Algebra" seems very un-Greek and very much Arab. What to do, what to do? Well, there is one book from Greek mathematics that kind of looks similar, the Arithmetica of Diophantus. It is not like other classic Greek mathematical texts - not very formal geometry like Euclid but a huge collection of problems on numbers with totally different notation then anything you've seen before. And so figures like Regiomontanus (real name Johannes Müller von Königsberg, where Königsberg means "king's Mountain", hence Regiomontanus) have a simple solution: the Arabs are really just doing Diophantus' stuff, but hiding it from us[6]. Maybe they have books Europeans don't. But that's not good enough for everyone. Like Viète.

But before we get back to our favorite mathematical-wizard[7], we need to talk about Pappus of Alexandria. Pappus is important to the history of math not because he invented a lot of new math, but because he systematized a lot of math known to him in 5th century of Alexandria, a summary of Hellenistic mathematical thought. And here he gives a vague description of "Analysis" as a method of discovering a proof, and "Synthesis" as writing down the deductive steps. Now, Viète read this and immediately saw an answer to his conundrum: Algebra was the secret method of Pappus, and thus really Algebra was Greek all along! And this is where he gets the odd names, they come from Pappus.

Of course there was no secret method at all, but Viète did add a lot to Algebra. He introduced the convention of using letters to represent unknowns, and set up Descartes to give us modern algebraic notation. Still very wrong about Pappus though!

[1] Please understand that here I do not necessarily mean followers of Islam or ethnic Arabs, but simply people involved in this cultural milieu. We know some of them were not Muslim like ibn Qurra (a Sabean), and some were not Arab like Al-Birumi and Al-Khwarizmi, both Persians. They all however wrote in Arabic in Muslim polities, and these seem to be the typical words used.

[2] Interestingly, the Omar Khayyam known today in the West for the Rubbaiyat was instrumental in attacks on the cubic using Conic Sections. A true polymath!

[3] His name would become our word "Algorithm" from the Latin version "Algorismus"

[4] This is why Al-Khwarizmi became so famous in Europe - his work was by then a little outdated in the center of Arab Mathematics in the area between Egypt and Iran, but Spain was a bit on the edge and so mostly had older texts. Plus he was quite systematic and easier to read than some books.

[5] And many other mathematical ideas like

[6] Thus continuing the cycle of people rediscovering Diophantus and declaring him the secret: the Arabs did it, then Regiomontanus, Bombelli, Fermat.

[7] The Spanish accused him of using "magic" to break their codes while he was France's cryptographer.

They wrongly believed that ancient architecture, statues etc were more or less grey, white and natural stone colour as ruins had lost their colour pigments. In reality ancient Egyptians, Greeks and Romans loved strong colours. (Most people would be shocked to see what ancient buildings such as temples looked like in antiquity). As a result, renessanse (and later ancient revival) architecture is largely grey or desaturated for that 'antique' look.

Source: Architect, studied art history where this is well known.