Killed the Emperor, yes. Sent the empire into ruin - no. Someone else would take the throne.
This. The Byzantines were amazingly reslilent.
Ok, maybe not a varangian emperor but a russian emperor that is helped onto the throne by the varangians?
Do you mean like Apsimar/Tiberius III? Basically as long as the new Emperor can pay the Varangians they are going to play ball.The ERE had several non-Greek/Roman Emperors, as I recall. Didn't a Gaul get onto the throne at one point? Or some sort of barbarian chap, anyway. A varangian taking the throne would not be entirely ASB.