When demanding Vassalization, how is the distance calculated
When demanding vassalization, a number of factors determine whether the other empire will accept your demand:
One of the biggest factors is "Distance". What does this distance signify?
It does not appear to be distance to my closest planet: in the screenshot bellow the only planet of this empire is in the same system as one of my planets (since I just liberated them, and I took over another planet in the same system in this war)
I don't think it is distance to my capital either, the system is fairly close.
As per this question How to get other empires to agree to "demand vassalization" peacefully? liberating planets should make it easy to peacefully vassalize them, yet this almost never seems to work in my case.
Here I reloaded and liberated a different planet in the same system. The distance stat appears to be gone. (Still not enough to demand vassalization unfortunatelly)
Best Answer
If you go to the Contacts > Empires tab, you'll see a 'Distance to' column. If you hover this number it should tell you the system that it is calculating the distance to from. For example, I was around 280 away from one Empire based of of my Home System, but I then colonized a system close-by and it changed to ~70 distance from that system.
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How do you demand Vassalize?
Making DemandsIn the \u201cEmpires\u201d tab, select the empire, click \u201cCommunicate,\u201d and then see what the \u201cDemand Vassalization\u201d button looks like. If it has a green tick, it means you can demand vassalization right now. If it has a red cross, however, there are some hoops you'll need to jump through.STELLARIS: OVERLORD - Essential Tips for Vassals and Overlords (Beginner's Guide)
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Answer 2
The distance thing certainly is a bug.
I also miss the opinion modifier for your vassalization request. A liberated empire should really like you and thus provide a big bonus. Considering,they have a friendly attitude, you certainly should get more positive modifiers than that. Another factor might be your empire ethics, which may prevent the vassalization. Peaceful vassalization works best with a xenophile empire.
In my personal experience of about 80 hours, I have to say the current diplomacy system is in need of a heavy rework, just demanding vassalization as a war goal is by far the most efficient way of expanding.
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Images: Ketut Subiyanto, Nout Gons, veeterzy, Mads Thomsen