I started this one as my first campaign in BI. Right off the bat you have to deal with a few cities that are suffering from some redness of the face if you get my meaning. That's because the settlement's official religion is Pagan, and it has a majority of Christians. Wreck the Pagan temple and build a Christian shrine in those cities. Stabilizing your internal situation should be your first concern, then you should worry about the Sassanids. You're at war with them at the start of the campaign.
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