How the Vargr have not Conquered Charted Space

Not Conquerors

This always bothers me. The Extents are huge. They are capable of large empires, regardless of how centrally weak they are, regardless of how they splinter or slowly degrade.  Empire is empire.

Charisma Problem

The reason, apparently, is because that not being human, their motives are not human either. They have this problem, which manifests itself in the game as Charisma. 

The problem goes deeper -- though I am not completely sure how to describe it. It was explained to me that Vargr have a need to follow the leader. Obviously this is how the Charisma mechanic works. The thing is, this drive is fundamental and goes all the way to their core. It's so strong that even leaders have this drive to follow the leader. This makes them susceptible to any strong sophont group which has Social Standing. And -- I think this is important -- specifically Social Standing.

Incomplete Understanding

It doesn't mean they just roll over to any human who shows up.

It doesn't mean they just roll over to any sophont with Social Standing, for that matter.

It doesn't mean they can't have empires -- obviously, they can, albeit typically short-lived ones.

It does mean they have a fundamental, genetic weakness in their empire-building skills.