The Hammer by K.J. Parker
Seventy years ago, a colony was founded on the western tip of an unexplored landmass. The colonists were supposed to mine silver, but didn't find any. Instead they farmed and lived in uneasy peace with the natives to the east. Later, the noble met'Oc family fled to the colony as exiles. Living on an impregnable plateau and raiding the colonists for livestock, they have not been the best of neighbours. Gignomai met'Oc, the youngest son of the family, rebels against his father and is disinherited, sparking a series of events that will define the future of the family and the colony. So, what do you call a novel which is not SF, which is set in an invented world but has no magical elements in it whatsoever, but where the spine of the book revolves around science and engineering? Science Fantasy? Fantasy Engineering? Of course, this is such a narrow field that you can simply call it a K.J. Parker novel and anyone who's read her* work before will know what you're talking ...