• Summary / Title: After winning a War my army is stuck and can't move
• Description: After winning a war with an attack during a siege, the army involved is now stuck in the territory
• Steps to Reproduce: 1. Siege a weaker enemy city  2. Attack and win  3. force surrender  
• Reproducibility: ?/?  has only just happened
• Expected Behavior: Move the army back to friendly territory or allow it to move out of opposing territory.
• Notes:
• Attachments: (When I did a screenshot (fullscreen), all I got was a picture of my Win10 wallpaper...) Sorry.

Yeah, I got it as well. It is slightly more general though. 

If the AI acquire a territory where some of your units are located for whatever reason, these units are not removed from the territory, and they can't move while losing health due to trespassing.

Fairly certain you can move them, but you must select a tile outside of the opponents territory to move to. 

So you got little to no control over pathing through the territory sadly

Yeah, I can confirm that, I saw it during my second game. However, while I get the idea (avoid to magically teleport armies outside of ennemy territory), I think it can be confusing and frustrating for newer players. Maybe add in the tooltip something like: "select a tile outside of the territory to leave"? But anyway, that's not really a bug then, just a confusing design.

I also had this happen to me. Even if you have open borders with another empire, you are not allowed to send troops through their districts it seems. The region I was in had a lot of mountains and districts of other empires blocked the only mountain pass routes back to my territory. I ended up having to declare surprise war and capture a city of a different empire to get my armies home.

Same happened to me. To be honest the armies should be moved automatically to the nearest owned territory. Because I had a situation where I lost my army then due to a long way back and AI always blocking the way out. This is somewhat strange after winning the war where I did not loose a single troop but while removing them from "non enemy" territory again I lost 7...