It has come to my attention that certain factions, "shadow factions" may not ever vassal for you.
For the purposes of this challenge, ignore making those your vassals.
Example: England won't have Scotland or France accept vassalage.
(Anyone who can refute this theory post proof)
So: for the purposes of this challenge, reduce them to a single province and keep them alive. That will be acceptible for your shadow factions.
It seems to me that Sicily will not vassal to Byzantium, either. May be why I am having trouble.
Anyone who can definatively prove that you can vassal your shadow factions, please do so. Anyone who believes certain factions will never vassal, also post here.
Lets determine an official way to deal with this issue.
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