What do we know about Vulgar Latin pronunciation?

Question

Nowadays, most Latinists learn the "reconstructed classical" pronunciation: an attempt at reconstructing the way Cicero, Caesar, or Vergil might have spoken in formal settings.

However, it seems fairly clear that this wasn't how an everyday Roman would have spoken in the forum. For example, Catullus 84 wouldn't make sense if /h/ was still pronounced in everyday vulgar speech. And later sound changes in Romance, like the loss of vowel length, probably didn't appear out of nowhere at the end of the Empire.

So: what do we know about how an everyday pleb would have spoken on the streets of Rome, somewhere around the first century? This question is unanswered, which I take to mean we don't know enough to make a full recording of it, but scholars certainly must know something about this topic.

Answer 1

It turns out, we know quite a bit about this!

There are three main sources for Vulgar Latin pronunciations: Classical texts imitating (or mocking or correcting) Vulgar speech, graffiti from actual plebs, and reconstruction from the Romance languages.

For the first of those, we have bits by Petronius and Catullus (the Cena Trimalchionis and Carmen 84), as well as the third-century Appendix Probī. And for the second, we have well-preserved writings from first-century Pompeii. These give hints at how Vulgar Latin was pronounced (by showing how it was spelled), and Romance reconstructions can fill in some of the gaps.

Here's a short summary of what I've found:

• H disappeared completely: harena → arena "sand"
• Qv merged into c before front vowels: coqvens → cocens
• Unstressed vowels in medial syllables (not the start or end of a word) disappear: spéculum → spéclum "mirror"
• Unstressed e and i turn into j before vowels: vínea → vínja "vineyard"
• V started being pronounced /v/ instead of /w/; later, b between vowels merged with it. (They both probably started as [β], but there's no way to know when that changed.)
• Nasals at the end of words and before s became nasalized vowels, then disappeared: consul → cõsul → cosul "consul"
• Consonants at the ends of words disappeared in some regions: graffiti in Pompeii has valeat → valja "may he flourish", but modern French still shows remnants of final ts, so this wasn't universal
• Vowel length was slowly turning into vowel quality: ī, ū, and o remained intact, while the pairs ō/u, ē/i/oe, ā/a, and e/ae merged into something like ō ē a e
• Diminutives were all over the place: fax → facla "torch", neptis → nepticla "granddaughter", ānus → anucla "old woman"
• Regular first/second-declension forms spread to other words: glis/gliris → glirus/glirī "dormouse", pauper mulier → paupera mulier "poor woman"

Answer 2

Not fluid, but I love paleography and got interested in scribal abbreviations and incunabula. Much of this is from Wikipedia.

Like in English, bad spelling betrays the pronunciation which changes over the decades.

The scholars complained all the time about the plebs and peasants talkin' like a bunch o' rubes gitt'n all them words wrong.

Thuh kid withowt uh dikshuneree wil spel it how it sownz, and yu can fynd it on sum grufeedee in Pompey. We can make a lot of guesses as to what happened:

•Vowel + n + (s/f) turned into nasal vowel + (s/f). "vocans" turned into vocãs. •A word with two or more syllables would lose its final-m "secundam" turned to "secundã". •a qu-sound before an o or a u would lose the u. "Quondam" turned into "condã" •H was dropped. In the Catholicon it isn't even considered a letter, but an "aspiration mark." "mihi" would need to be spelt "michi" or it would be pronounced mî. •most ae and oe turned into monophthongs. In Greek, αι became ε and ε became "ε ψιλον" (plain e). οι became υ and υ became "υ ψιλον" (I think it was first pronounced like a ü and eventually another i). Latin later did something similar. If it was kept a diphthong, you put a trema over the other vowel like in greek. ære for bronze, aëre for air. Eventually both were often spelt with a little tail on the ę to save precious parchment, and quit caring which was which. "Cœlum" was written "cælum". •when it made speaking easier, i or e before another vowel would turn into a consonant i and sometimes stress its vowel. "cuius" turned into "cujus". •I think a lot of "vi"s in the middle of words dropped. Novisti turned into nôsti.