For my storyworld, which I'm still trying to figure out a good name for ironically enough, each culture/country is more or less based vaguely off of the a subgroup of folklegends. I tend to base the names and words in general off of what would be a feasible linguistic progression if contact were made between the different languages of the folklegends, or general bastardizations of prevelant parts of the folklegends. (Yesh, I'm a MAJOR linguistics nerd... ConLangs and all) For example the continent where the majority of my stories are set at the moment, the Maelyarian, is based off of mostly Celto-Franco-Ibero legends and so most of the real names for those countries are based off of those languages... Although does anyone else use placemark names if they can't think of one that's completely right at a time? IE inserting a completely obvious stock fantasy-name until you can come up with one that fits better?