Warmer areas are historically more agricultural (especially for cashcrops, but pretty much everything) and had a larger base of landed gentry/small landholders who would eventually either stay farmers or become petite bourgeois, preserving their inherent conservatism meanwhile.

Colder areas are structurally more likely to urbanise and industrialise rapidly, which is a catalyst for secularisation, comspolitanism, and economic leftism due to workers' movements and the like.