Ooh, /u/yodatsracist gave me an amazing answer to a similar question on ethnic/geographic-based conflict in Myanmar or Burma and its relationship to British imperialism.

These sorts of highland/lowland conflicts have been going on roughly since states emerged in the lowlands, though they have taken many, many forms over the years. Today, paved roads, all terrain vehicles, and helicopters have given the lowland states power in the highlands that they never had before and many of these highland groups that have been traditionally outside of the state system (or who have been part of an alternative state system) have been fully brought into the state.

Go read more and give /u/yodatsracist the upvotes!