@ValeOfShadows > as they being the true inheritors of the Roman Empire believed, Italy and Rome should be under their control(this tension would also eventually cause the Catholic and Orthodox Churches to split many decades later in the Great Schism).

Thank you for recognizing that the Eastern Roman Empire was still the Roman Empire - that detail gets lost in a lot of summaries on the subject !
The *other* cause of the Great East/West Schism was internal to the Western Church - wherein a small but focused consortium of power-hungry clerics and monks seized upon certain “innovative” distortions present in Blessed Augustine’s treatment of Original Sin - wherein he argued we inherited not merely the Sin of Adam, but *also* his Guilt. This justified to them a reworking of the Traditional Church Hierarchy, that long-story short, caused Papal Supremacy to emerge.
The only reason I mention it is because the political situation likely would not, on its own, have caused the Schism. But the combination of simultaneous political and spiritual divisions sufficed to wedge The West out from the rest of Christendom.
In any event, excellent overview; thanks again !