There was a tory council in Liverpool in the very early seventies, quite easy to dig out. It's been a "left" city with a couple of anomalies for most of the last century though.
As Craner said- sorry for paraphrasing- the NIP are trying to coerce a conceptual divide here without really understanding the nuances I think.
I know all of this. One can still be proudly left wing and proudly British though.