[bnralt]

To go even further: I imagine if the Arab world was politically unified with Europe today, there'd be a lot of people saying that it was always a unified Mediterranean cultural entity, sharing Monotheistic Abrahamic religions, Greek intellectual foundations, and having a long-term shared history in the Roman world. It's not a point of view commonly encountered today, though, probably because Europe and the Arab world aren't politically unified.

That is to say, if you decide that a region should be seen as unified (perhaps because of modern political boundaries), one can cherry-pick common elements to try to reach that conclusion. It's not entirely incorrect, but it's a biased way of presenting the evidence in order to justify a preconceived belief.