[kragen]

"West is essentially a Roman affair"? I don't think that's true at all; intellectually, Roman civilization was almost entirely sterile, appropriating the Hellenistic cultural heritage and then totally failing to progress for centuries, even backsliding in many ways. And, despite the importance of Aramaic, Greek was a much more important lingua franca, continuing to be so until the fall of Byzantium.

It's true that the division between the Eastern and Western Roman Empire created a new East/West divide approximately corresponding geographically to the old Greek/Persian divide.