Worldbuilding

My background on the subject is not deep, but I am given to understand that national borders came into existence with the idea of the "nation state", and not all borders came into existence at once: https://vividmaps.com/the-age-of-borders/

If you look over old maps, it seems there was less emphasis on borders, and more emphasis on named areas, roads, rivers, etc. The implicit choice of what area your map covers is enough context to address the idea of a border. After all, if your map is 'diegetic' (made by someone from inside your world) it was made with implicit political and cultural leanings, or even an overt agenda. In my early maps of my world, there was a town labelled "Aphallon" even though it was only called that during a colonial occupation and is considered deeply uncouth to refer to that town as such now. I eventually went back and changed it, since my map is not diegetic. It would be fun to make a series of maps that live inside the setting, but my cartography workflow is too labor intensive for it right now so I'm deciding to make my map a more neutral "outside looking in" sort of device.