How to create periods

[Epistolary Richard]

You can do it with a further mod, as with TFT, or a simpler way would be to just have a Provincial Campaign. A Provincial Campaign is a lot easier, but it limits what you can mod to an extent.

This answer to this question is very obvious to those who know about modding, and it requires me explaining quite a bit just so you do. You will be able to figure it out if you just read some guides on making campaign maps and try them out.

Perhaps not the most helpful answer that's ever been posted in this form.