The original residents of Thailand are believed to have been Negritos in prehistoric times of Melanesian origin; the fertile plains subsequently attracted Paleo-Indochinese peoples, in particular the Khmer, the current residents of Cambodia. But destined to have the upper hand were the Thais, who came from the North in successive migrations and practically in the century. XIII occupied the country, concentrating mainly on the Menam plain and in the intermontane basins. Almost all of the population today is made up of Thai people (the small minorities are grouped in the peripheral areas); under the name of Thai, however, different peoples are included, united by the fact that they speak the same language, belonging to the Sino-Tibetan family. The Thai population is ethnically divided as follows: Thai 95.9%, Burmese 2%, Cambodians 0.4%, Laotians 0.3%, Chinese 0.2%. In addition to the actual Thai, or Siamese, the Lao (who live mainly in nearby Laos) belong to the same lineage and in Thai territory they are particularly widespread in the Khorat and the northern mountains, where scattered groups such as the meo and the yao are also settled; also of Sinic origin, they practice itinerant agriculture by resorting to the practice of burning forest areas (ray); in addition to cultivating rice, corn and opium, they are dedicated to the breeding of pigs and horses.
According to localtimezone, Karen tribes live in western Thailand, of Burmese origin, while Malaysian people predominate in the southern region; here, in the shelter of the dense forests, small nuclei of semang still survive, the most primitive of today’s residents of Thailand, hunters and gatherers similar to the mincopi of the Andaman. The migrations that began towards the end of the century XIX at the time of the creation of the railway network we owe the presence of Chinese in Thailand, mainly engaged in commercial activities; it is a well integrated community with good political representation. The case of the Malaysian minority of Islamic religion, based in the southern region, which is poorer and more discriminated, is different. There are also over 100,000 refugees from Myanmar who are fleeing ethnic discrimination. Family planning campaigns and increased living standards and education have contributed, since the early 1990s, to lowering the birth rate and reducing the rate of population growth. However, the population density is constantly increasing: if at the 1980 census there was a population density of 90 residents / km², in 2015 it was 135.87 residents / km². Naturally it is the presence of environments suitable for rice growing and climatically favorable to determine the laws of population. Thus the densest concentrations correspond to the Menam plain and to the southern area close to the delta. The flat areas that lie immediately at the foot of the hills are also populated; large areas of the country, such as the mountainous north, are however sparsely populated; in the plains themselves there are densities not high far from rivers, which represent the main and traditional axes of attraction. Two thirds of the population live in rural areas. Among the forms of settlement predominates the village consisting of wooden houses on stilts: the main building is the wat, buddhist temple and monastery. The villages arise mainly along the waterways, natural communication routes; among the mountain populations who practice itinerant agriculture there are numerous, precarious villages located in the middle of arboreal clearings and formed by a few wooden huts. The cities, which arose with the formation of the first Thai kingdoms, served as seats of civil and religious power and maintained their importance only for the period in which they played this role: this is especially the case of Ayutthaya, the ancient Thai capital. The only metropolis is Bangkok, a city of relatively recent foundation and capital since 1782.
Located on the left bank of a meander of the Menam just 30 km from the sea, it owes its fortunes to a large extent to the process aroused throughout the Indochinese peninsula by commercial relations with the West. which led to the abandonment of the ancient capitals settled in the heart of the river regions to the advantage of coastal centers or easily reachable by water from the sea and this for obvious commercial reasons. Around a nucleus of monumental imprint, with public buildings, temples and palaces that refer to the Thai architectural tradition, a vast city has now expanded, with a real city modern but also with endless and miserable neighborhoods of hovels: almost a synthesis or a symbol of the contradictions that the country is unable to heal. In recent decades, the expansion of the city has been significant, thanks to the new activities, including industrial ones, which have sprung up and created one of the largest urban agglomerations on the continent which already hosted over 8 million people in 2010; Bangkok is the largest commercial and cultural center in the country, as well as a primary communications hub. In the provinces around the capital there are other important cities, such as Samut Prakan, Nonthaburi and Nakhon Pathom. The other centers have only regional functions, such as Chiang Mai, the largest city in the Northern Region, or Nakhon Ratchasima, the hub of Khorat and located in the north-eastern region, and Udon Thani, the most populous center in the same region, Chon Buri, the largest center in the Eastern Region, or Surat Thani, the port of the Malay peninsula.