Castles don't stop armies from advancing, right ?

[Gandalf Parker]

There is a pro and con to this concept also. People complain about lack of alliance options but the present castle arrangment allows you to let ally armies pass thru your territory. Ive used castles provinces as doors thru my territory since at least early Dom2

[lch]

More micromanagement, yay!

[Kamamura]

Contrary to original post, I think that it's completely realistic that the army retreating to the castle loses control over the province.

Historically, the defender either met the invader in the field with the chance to save the villages in the countryside, or retreated to the castle. In latter case, the invader surrounded the castle, cutting supplies to the castle (siege), while his marauding parties pillaged and burned the countryside. The defender could only watch from the walls.

So the castle is not "ignored", it's besieged.