Several problems with this idea. I cannot think of any state during our timeframe that could be classed as "brigands or pirates", it follows therefore that any state represented by a rebel province could be traded with. Thus it would follow that every state would be of these "free cities with wich u may commerce". However by electing to make this faction a full faction and allow diplomacy to act upon it then all diplomatic options are open - and this is the big problem - it thus allows a player or AI faction to be at peace with a large proportion if not all the rebel factions.

This has been discussed and it has been rejected.

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