> For the biggest differences: by the time of Basil II they were speaking Greek instead of Latin As far as I understand it, the lingua franca of the Eastern Ro

> For the biggest differences: by the time of Basil II they were speaking Greek instead of Latin As far as I understand it, the lingua franca of the Eastern Roman Empire never “changed” to Greek, it was always Greek in the first place. “During the earlier Pax Romana period, the western parts of the empire became increasingly Latinised, while the eastern parts largely retained their preexisting Hellenistic culture, creating a dichotomy between the Greek East and Latin West.” https://en.m.wikipedia.org/wiki/Byzantine_Empire https://en.m.wikipedia.org/wiki/Byzantine_Empire