Which is the most correct latin pronunciation? I mean, did they have the same accent as italians or other modern neo-latin languages speakers? Do we even know??
"Correct" isn’t really the most correct word to be using here, because there are several "correct" Latin pronunciations—four, actually.
- Classical Latin - the pronunciation used by the Ancient Romans. As such, it’s the pronunciation taught in schools today (thanks to the Renaissance). This was pretty much identical to modern English except v's were always pronounced like u or w (the Romans didn’t have either of those letters), ae sounded like aye (cry), c always sounded like k and never s, g never sounded like modern j, j wasn’t a letter but i could be used in its place (sounding like consonantal y). There are a couple of either changes, and you can read those here. As for how we know that this is how the Romans pronounced Latin, W. Sidney Allen published Vox Latina in 1965, detailing the reconstruction of classical pronunciation. His arguments included that the Roman alphabet was intended to be purely phonetic so that you could perfectly predict how the word would be spoken just by reading the word. We can read surprisingly detailed explanations of the Latin language from classical authors themselves. Common misspellings can provide clues to the pronunciation of the word. We can compare Romance language pronunciations to each other. There’s more, and you can read about that here.
- Medieval Latin - When the Roman Empire expanded, so did the reach of Latin. Latin was influenced by many local languages, including German. We know it was about this time that j (pronounced like the consonantal y) entired the language, and diphthongs were contracted (ae became e, so we can assume that it was now pronounced like e). Latin also started forming local dialects, which evolved so intensely that we now call them different languages. This was the origin of the Romance languages.
- Church/Ecclesiastical Latin - the Latin of the Catholics. This is where a lot of modern misconceptions about Latin pronunciation stem from. The Catholics determined that, for the purpose of Mass, Italic pronunciation just sounded better. Vowels were no longer long or short, c could sound like ch or k, g could sound like the modern j sometimes, j sounded like y, v sounded like the modern v, and some more. You can read about that here. Church Latin was only used for church purposes, however.
- English/Business/Legal Latin - the pronunciation used today when people want to sound smart by using Latin words and phrases but don’t actually sound smart because they don’t know how to pronounce Latin. English Latin simply pronounces Latin as though it were English, with ending i's in plurals sounding like aye (even though that was never a thing in either Classical, Medieval, or Church Latin.
Hope this helps, Anon!