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What if Robert Guiscard had not went to the aid of the Pope against the HR Emperor and had instead focused his efforts on Byzantium. With a bit of luck, Alexios is slain allowing Robert Guiscard to roll through the Balkans laying siege to Constantinople before the city surrenders and he is crowned emperor. And what if after his death (which would be delayed), Bohemond is able to secure his own position as emperor maybe by taking a Greek as his wife and fighting against Roger.
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