what type of states politically/culturally would "Northern California" & "Southern California" be?

[The Right Honourable Martin Brian Mulroney PC CC GOQ]

It's possible that they would have evolved in divergent directions, and in fact they kinda were in the past - NorCal has pretty much always been a liberal bastion, but SoCal used to be quite conservative until the 1990s. But nowadays, most places with a high degree of urbanization are liberal, and SoCal would have been urbanized regardless of whether it was in the same state as NorCal. Maybe in that scenario, SoCal would attract more conservatives and be like Arizona, strongly Republican until recently when the trends kicked in and Democrats started winning. But I think even that is a bit of a stretch. I don't think they would be that different politically than they are IRL.

Culturally, again I think it would be similar to current NorCal/SoCal divides, but perhaps more pronounced. Which is to say, NorCal would feel even more like a northeastern state than it already does, and SoCal would be more Sun Belt-y than it already is.

[The Right Honourable Martin Brian Mulroney PC CC GOQ]

Culturally, again I think it would be similar to current NorCal/SoCal divides, but perhaps more pronounced. Which is to say, NorCal would feel even more like a northeastern state than it already does, and SoCal would be more Sun Belt-y than it already is.

I don't really think of NorCal as being culturally similar to any part of the Northeast- not least because California seems to define itself in opposition to the entire country east of the Rockies. Agree with you on the politics aspect.

True I think the PNW would have been a much more obvious comparison. Although a part of the reason why the PNW/NorCal are as progressive as they are was, historically, a mix of Yankee and Irish migration and general western populism. My understanding is that SoCal saw more Southern and later Midwestern/Plains (i.e. many conservative Germans) migration, again a bit more like Arizona, which created a more conservative culture in the mid-20th century. I could be wrong though, I'm a little rusty on California settlement patterns.