>>Latin was the preeminent language of Roman civilization from the republican to imperial era.

Post the Roman conquest of Greece (146 BCE) there was something of a Greek cultural takeover of the Roman Republic. Upper classes tended to speak Greek (their tutors being slaves from Greece).

I got interested in this after wondering "What did Caesar *really* say to Brutus (who was likely an illegitimate son) that unfortunate ides of March?"

Suetonius writes that Caesar said "καὶ σύ τέκνον" (Kaì sý, téknon) - You too, [my] child.

My point here is that a Roman would speak his last words in Greek - not Latin - and a historian of that era would find the use of Greek unremarkable.

Personally, I would have expected Caesar to have used Brutus' praenomen (personal name) but I could find no historian who claimed that.

Oh, and there's now a Wikipedia page on this https://en.wikipedia.org/wiki/Last_words_of_Julius_Caesar

Because of course there is...