The Hinterlands aren't quite a region, but it isn't quite a battlefield. It is the land between the Dark Fortress and the Bastion of Enduring Light. There were a lot of villages and small towns that were abandoned in the War Against the Night, but people are starting to move back. However, those small villages are now in various states of ruin, occupation, or reclaimed by nature.
Many of those refugees inhabit Bastion of Enduring Light and Base Camp.