latin high

“During the era of Marcus Aurelius, [Roman emperor Marcus Aurelius Antonius Augustus, A.D. 121-180] the separation between High Latin and Vulgar Latin was already noticeable. Now, High Latin would be what we consider Received Pronunciation. It was less and less anyone’s mother tongue, but rather something which was learned and considered as a status sign. Everyone else spoke Vulgar.”
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“We do not know when the last native speaker of High Latin died. Most likely it happened sometime in the 6th century. But we can say for certainty that Vulgar Latin superseded High Latin as spoken language. High Latin remained only as the language of written documents.”

Susanna Viljanen, Quora contributor, Aalto University, Finland