Don't worry we can always take the sea route... they'll never see it coming. 
Honestly, attacking via sea routes would probably be a bad idea against Nivemus, and that's even if you were successful. We have two huge rural regions, a townsland, and a city all on the coast. The townsland and the city will obviously have walls and militia so you don't want to land there. One rural region is a turn away from our capital, the other two turns away. And there are only two of those regions. Let's suppose we put a force of militia in Juazeiro. Then, once again, heavy, heavy casualties to land there. The other one is right next door to our capital.
Yeah, Nivemus is pretty well defended so far as the sea route scenario goes, and quite honestly, I think a sea attack would be way too dangerous for Westmoor to do on us if they declared war on us anyways. They can hit our rural region and one of our less meaningful regions while we rape either your capital or Oligarch. Then, we move back, refit in our capital, and smack your army down before you can head back to Westmoor-land. Not very fun.
Quite honestly, this whole sea route attack is a very, very, very high risk attack. But, if done successfully and well, it can tip the balance of a war in your favor tremendously as well. I am still waiting on two realms being in each others capitals though. That would be hilarious.
