The historic counties of Northumberland, County Durham Cumbria, Lancashire, Cheshire , the historic ridings of Yorkshire and in addition the unitary authorities of North Lincolnshire and North East Lincolnshire. Which incidentally more or less consists of the following Euro constituencies/English regions: North West England, North East England and Yorkshire and the Humber.
I'd largely agree with you here,
mikeg. Slight suggested adjustments: my parents were from Chester city or just outside of same, and they identified themselves and their area of origin, as Northern. I kind of gut-feel, though, that the county of Cheshire should be split, re regional characteristics: the northern half of it, counting as part of the North; the southern half more akin to the Midlands / the Welsh Marches. Somewhat the same with (as you mention -- second quote from you, below) Derbyshire, which bulges quite a long way up northward -- to Woodhead and a little way beyond; in connection with which, the Peak District strikes me as definitely Northern, except maybe for its limestone southernmost fringes.
I like to imagine, dividing the North of England from "the rest", a straight line running approximately west-south-west, from Cleethorpes to the Welsh border just south-and-west of Chester city.
Thinking about it, Lincolnshire's a funny county, I associate most of it with being in the East Midlands, the unitary authorities as being in the North, along with maybe Lincoln at a pinch and the South Eastern extremities as being practically anglian.
I agree with (my bolding, above !). I was born and spent my early childhood in the Fenland far south of Lincolnshire (my parents were "exiles" there). For sure, no way can that area feel like or be counted as "Northern".
The closest equivalent in this sense I can think of is Derbyshire, North West Derbyshire areas in the North West, Northern bits are almost an extension of Yorkshire, most of it in the Midlands, most East Midlands but some almost bordering on West Midlands.
Edit: Do we consider there to be a Midlands zone or do we just have north and south?
Cities like Birmingham and Nottingham are by no means Northern, but they aren't Southern either. So yes, the Midlands is a thing.
I'm with all who opine that it is indeed not just north and south -- there are intervening zones with their own definite traits. I could never envisage East Anglia, or the Midland areas running westward therefrom to the Welsh border, as "the South". I might venture to suggest that the River Thames, throughout its course, marks the northern limit of "the South": which -- at location(s) which could be argued over -- ultimately merges / transforms into the West of England.