I had read that during the Roman empire there was a lot of Latin-Greek bilingualism, and that an educated person would be expected to know both, even in the wes

I had read that during the Roman empire there was a lot of Latin-Greek bilingualism, and that an educated person would be expected to know both, even in the western part of the empire. At some point that ceased to be the case and those places just got Vulgar Latin and the various Romance languages.