Within takes place in Denoril, also referred to as the Land of Five Provinces.  Here's a closer look at the map, designed by artist Francesca Baerald.

Denoril is ruled by the Council of Lords.  Each ruling council seat is designated by the Earl of one of the five provinces.  The five provinces are: Barden's Reach, The Dagger Coast, Karnell, The Boroughs, and New Dilith.