How can I capture "No faction" cities?

[AlxGvr]

I was in war with Brycheiniog, this faction had only one city... Brycheiniog. And two lords. I have captured and executed them both. The city became "No faction" and I can`t besiege it anymore. We are friends now. And I can`t declare war, because there is no such faction.

Is it a bug?

 

[manekemaan]

go in cheatmode, enter the town and besiege it

 

[Idibil]

I was in war with Brycheiniog, this faction had only one city... Brycheiniog. And two lords. I have captured and executed them both. The city became "No faction" and I can`t besiege it anymore. We are friends now. And I can`t declare war, because there is no such faction.

Is it a bug?

jur, maybe we shouldnt let kill kings, no?