In the past, much was written of the Holy Empire. This is important, for as opposed to the Lands of Night, the Lands of Light share a common history--a brief one, in parts, it must be said--as one state. The closest equivalent in the Lands of Night would be the era of the Amontides' preeminence--and even at the height of Sutekh's rule, they didn't not rule all of it. For the Lands of Light, the Empire unites them into a common nation--it is something that all the states in it define themselves in relation to.
No matter how deceptive that may be.