Ah, you're playing as the Casse. There are two free armies there, both mean trouble but one of them is really powerful for a starting Casse. It's better to take the southern part first, then march north to fight these armies before laying siege. They'll come to chase you away if you stay in free territory up north. There's no shame in retreat if you make enough casualties to be able to take it the next time around.
Edit: Eleutheroi have their own economy to be able to do anything even with all the roaming stacks.
Edit2: You might want to find an AAR or guide to the Casse in that subforum.
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