With the caveat that B and C were more like B through J or so. The pre-existing tribal nations that were adjacent would give you something very much like this, though. (B used to live on that side of the river, C on this side, and everybody from the other tribes isn't all that welcome around here.)

Of course, in that case, everyone wound up speaking Latin in the end and forgetting that they had ever been anything other than Romans.

-- Graydon