The Free Cities
When The Empire sued for peace, the major contested points where those large settlements now known as the Free Cities. The empire wanted control over them, the coalition would have none of it.
Knowing it didn't have the resources to continue to fight, the empire had to give in, so it suggested they each become independent city states, which was accepted by all.
Of course, in reality, the city states are like client states to the empire even though they are technically independent.
The Free Cities are independent city states, at least nominally. In truth, politically, they mostly follow what the imperial ambassador tells is in the empire's best interest.
Mostly imperial or Heregonian (hill people) names.