The Khmer Loeu (Khmer: ជនជាតិខ្មែរលើ [cunciət kʰmae ləː]; "upper Khmers") is the collective name given to the various indigenous ethnic groups residing in the highlands of Cambodia. The Khmer Loeu are found mainly in the northeastern provinces of Ratanakiri, Stung Treng, and Mondulkiri. Most of the highland groups are Mon-Khmer peoples and are distantly related, to one degree or another, to the Khmer. Two of the Khmer Loeu groups are Chamic peoples, a branch of the Austronesian peoples, and have a very different linguistic and cultural background. The Mon–Khmer-speaking tribes are the aboriginal inhabitants of mainland Southeast Asia, their ancestors having trickled into the area from the northwest during the prehistoric metal ages. The Austronesian-speaking groups, Rade and Jarai, are de