Slitherine

First time playing, so possibly I'm not "getting" some sort of game restriction, but the next turn after taking Vienna as France, there's a one hex perimeter surrounding Vienna that I can't move into. Also, there's an Austrian Line Infantry unit "stuck" in this perimeter. Vienna itself says the owner is France (nationality is Austrian in parenthesis), and I can wagon move into it, but can't move through the perimeter of Austrian-owned hexes, nor can I attack that sole Austrian unit.

nm, just RTFM on the section on vassals.