Once you have a Casus Belli on an entire duchy, you can declare war for it, and take it all at once. For it to be clickable, you have to have 100 piety, the pope must love you, and hate the other guy. Go to the title screen, and at the top are several different buttons, one of them is 'demand'. You often gain a claim for that county, but sometimes, with a chancelllor with 15 or 20 diplo, you might gain a claim on the entire duchy ). To gain claim, again, two main options: you can fabricate one via your chancellor ( place it on the capital county of a duchy, then wait. Strong claim mean you can declare war anytime, weak claim mean you have to wait for the ruler to be in regency, or to be female. If you have a claim on a title controlled by some one else, you can declare war for it, depending on the type of claim. If you control a duchy, but a dejure county within it is out of your control, you gain a CB on the controller of that county ( meaning if you delcare war on that CB you'll get that county, and that county ONLY! )
Enforcing demands mean end the war and gain what you declared the war for.Īs a same religion ruler as your oponents, you get two main choices: YOu have to pay attention to which casus belli you use to declare war.