Thailand is a country of some 70 ethnic groups, including 24 groups of Tai peoples. The Thai (or ethnic Tai/Dai) and Thai Chinese make up approximately 90% of the nation's population of approximately 67.5 million.
Khmer and Mon-Khmer make up approximately 6%, the Malays of southern Thailand make up around 3%. Among the groups categorized as hill tribes in the northern provinces, Hmong (Mien), Karen and other small hill tribes make up around 1%.
In official Thai documents the term "hill tribe" (chao khao) began to appear in the 1960s. This term highlights a "hill and valley" dichotomy that is based on an ancient social relationship existing in most of northern and western Thailand, as well as in Sipsongpanna and northern Vietnam. For the most part the Dai/Tai/Thai occupied the more fertile intermontane basins and valleys, while the less powerful groups lived at the less rich higher elevations. This dichotomy was often accompanied by a master/serf relationship.