The population of Myanmar took place, as in the whole Indochinese area, following the descent of people of Tibetan and Chinese origin from the mountains and the northern valley towards the plains, where they overlapped the pre-existing groups of Indonesian origin. The central plains represent the true heart of the country and one of its even more populated areas, although interests have shifted towards the Ayeyarwady delta, in particular towards the capital Rangoon. In these regions there are densities that are decidedly higher than the average (73 residents / km²) – even seven times in the State of Rangoon – and naturally the lowest ones are found in the mountainous areas; these same areas provide continuous demographic contributions to the plains, according to the movement of past centuries, made easier by modern organization of the state, although the recognition of distinct nationalities represents a brake on the fusion of ethnic groups. Among these, the Burmese or Myanma (55.9% of the total) who populate the plains of Ayeyarwady largely predominate; the strongest minorities are represented by karen or kawthoolei (9.5%), a Sino-Siamese group that is concentrated NE of Rangoon, in Tenasserim and in the Salween valley, and by the shan (6.5%), of Chinese origin, who populate their plateau and they are divided into about forty feudally organized principalities; in the last two decades of the century. XX the Karen populations have achieved greater ethnic cohesion, a fact that has worried the central government in such a strong way as to push it, starting from the mid-nineties, to activate a series of persecutions through the regular army: hundreds of thousands of people they had to leave their villages and many of them found refuge in neighboring Thailand. The other important groups are those of the chin (2.5%), living in northwestern Myanmar, kachin (1.5%), settled in the far north, and kayahs, in the middle Salween valley. Small groups live in the mountains that have long remained unrelated to any cultural relationship with the Burmese: this is the case of the naga, the kamti, of the va. The Arakanese, farmers and fishermen, instead gravitate towards Bangladesh.
According to localtimezone, most of the population lives in villages among the rice fields, with wooden houses usually resting on poles; on the mountains and outside the areas where there is seasonal flooding of the rice fields, the houses, also in wood, are built directly on the ground. These centers are found for the most part along the rivers, especially along the Ayeyarwady, as the river route is still the most used and congenial to a State that arose in close dependence on the rivers. The urbanization rate, a phenomenon that became significant only in the 1970s, continues to be very low: less than a third of the population lives in the city. The main center is Rangoon, the capital, flanked by the huge military base of Mingaladon; its port, which has been one of the most commercially developed in the Southeast, has seen its activity considerably reduced. Second by population is Mandalay, formerly a sacred city, a communication hub of primary importance, a woodworking center and a market with a vast hinterland. The other main cities are mainly located on the coasts and have developed as port centers: such is the case of Moulmein on the Tenasserim coast, with huge shipyards for wooden ships, of Bassein, in the Ayeyarwady delta, a rice center, and of Sittwe (Akyab), on the Bay of Bengal. Among the cities of the interior we can mention the Shan markets of Taunggyi, Pegu, Möng Mit, Kalaw and Pindaya; on middle Ayeyarwady, Pagan is famous for its thousands of pagodas.
The vegetation varies according to the altitude and rainfall. The typical monsoon forest, rich in precious essences, is located on the wettest slopes of the Arakan; in many areas it appears however by now degraded and is replaced by a savannahdominated by ferns and bamboos and by a typical grass, the alang-alang, of the Arundinaceae. On the reliefs, above the monsoon forest, there is the oak forest and further above, over 2000 m, that of conifers (cedars, etc.); mangroveformationsinstead they border the coasts. The forests, which cover half of the territory as a whole, are home to a rich fauna (tigers, leopards, elephants, monkeys, rhinos, parrots, pheasants, etc.). In the coastal areas there are turtles and a very varied fish fauna. Deforestation and pollution of water, land and air are among the environmental issues that the country is called to address with greater urgency. 5.9% of the territory is protected in various ways: there are 6 national parks including the marine park of Lampi, the Alaungdaw Kathapa park and the Nat Ma Taung. The relevant legislation is aimed at preserving the remarkable natural heritage and promoting ecotourism.