Really interesting segment at the beginning of Mark Whittow's "The Making of Orthodox Byzantium". He is outlining the position of the Roman Empire in 600 (chapter 3), and specifically talking about the Monophysite controversy. His point is that historians have overplayed it's significance. In fact, differently nuanced Christians had more in common, and this gave them a common identity when compared to non-Christians. In fact, even provincial citizens considered themselves 'Christian' and 'Roman' rather than from smaller ethnic groups. There is a clear shared culture (but is this just the elite?).
In other words, this is Byzantium's historic achievement - to weld a cohesive state out of disparate parts, something which modern nation states seem very unsuccesful at doing.
