Peopling of Laos

The peopling of Thailand refers to the process by which the ethnic groups that comprise the population of present-day Thailand came to inhabit the region. Aside from ethnic groups representing recent expatriate migrations, and the earliest Negrito arrivals, the ethnic groups of Thailand are all believed to be descended from ethnicities associated with clades of Y-DNA Haplogroup O.

This suggests an ancient homogeneous ethnicity in Southeast Asia some 35,000 years ago which, over time, spread out and independently evolved into diverse sub-ethnicities, branches of which found their way to Thailand at different points in history, employing different migration routes and modes of transportation, only after being infused with elements of other cultures along the way, via both exposure and inter-breeding. The result is an extremely diverse population of distantly related tribes with a common Asian heritage steeped in ancient tradition.

The Sayams are an indigenous tribe of southern Thailand, who make their home on the Malay Peninsula. Although they now speak a Mon–Khmer language, they are not a Mon–Khmer people, but are a remnant of a much earlier migration into the region. The Mani are the only Negrito people living in Thailand. This was proven when the Thai and Australian governments conducted DNA tests on them.

The Negritos are among the least-known of all living human groups, and their origin is much debated. The Malay name for them is orang asli, or "original people". They are most likely descendants of the indigenous populations of the Sunda landmass and New Guinea, predating the Mongoloid and Australoid peoples who later entered Southeast Asia. Alternatively, some scientists claim they are a group of Australo-Melanesians who have undergone island dwarfing over thousands of years, reducing their food intake in order to cope with limited resources and adapting to a tropical rain forest environment. Regardless of the theory of origin, geographically speaking, they probably came to Thailand via the lower portion of the Malay Peninsula, through present-day Malaysia.

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