Hey, Raphael, thank you for your comment!
To occupy a province your country must border it. For example, as USA you can easily occupy Monterrey:
Also, there's may be a bug in province's adjacency. Can you clarify on which country you played with and what province you can't occupy?
That's sounds like you had an army size smaller than those provinces' defences. To occupy a province you need to recruit an army big enough. For example, if you want to occupy Monterrey as USA you need to have 50 army points, because Monterrey has 50 defence points.
Edit: Also, maybe you ran out of gold.
Oh, to occupy a province it doesn't matter how many army points is in your bordering province, only thing that matters is your country's army points (see top menu):
Oh okay, thank you. I'll try again and see if I can figure it out. But I do think there should be more of an indicator of this in the game so people won't have to go looking through the discussion board.
