Tibetans are distributed over the entire Tsinghai-Tibetan plateau. Outside Tibet, Tibetan minorities constitute au­tonomous prefectures and autonomous counties. There are five Tibetan autonomous prefectures in Tsinghai, two in Szechwan, and one each in Yunnan and Kansu. The Tibetans still keep their tribal characteristics, but few of them are nomadic. Though essentially farmers, they also raise livestock and, as with other tribal peoples in the Chi­nese far west, also hunt to supplement their food supply. The major religion of Tibet has been Tibetan Buddhism since about the 17th century; before 1959 the social and political institutions of this region were still based largely on this faith. Many of the Yi (Lolo) were concentrated in two autonomous prefectures—one in southern Szechwan and another in northern Yunnan. They raise crops and sometimes keep flocks and herds.

The Miao-Yao branch, with their major concentration in Kweichow, are distributed throughout the central south and south-western provinces and are found also in some small areas in east China. They are subdivided into many rather distinct groupings. Most of them have now lost their traditional tribal traits through the influence of the Han, and it is only their language that serves to distin­guish them as tribal peoples. Two-thirds of the Miao are settled in Kweichow, where they share two autonomous prefectures with the T'ung and Puyi groups. The Yao peo­ple are concentrated in the Kwangsi-Kwangtung-Hunan border area.

In some areas of China, especially in the south-west, there are many different ethnic groups that are geographically intermixed. Because of language barriers and different economic structures, these peoples all maintain their own cultural traits and live in relative isolation from one an­other. In some places the Han are active in the towns and in the fertile river valleys, while the minority peoples depend for their livelihood on more primitive forms of agriculture or on grazing their livestock on hillsides and mountains. The vertical distribution of these peoples is in zones usually the higher they live, the less complex

their way of life. In former times they did not mix well with one another, but now, with highways penetrating deep into their settlements, they have better opportunities to communicate with other groups and are also enjoying better living conditions.

While the minorities of the Sino-Tibetan language fam­ily are thus concentrated in the south and south-west, the second major language family the Altaic is represented entirely by minorities in north-western and northern China. The Altaic family falls into three branches: Turkic, Mon­golian, and Manchu-Tungus. The Turkic language branch is by far the most numerous of the three Altaic branches. The Uighur, who are Muslims, form the largest Turkic minority. They are distributed over chains of oases in the Tarim Basin and in the Dzungarian Basin of Sinkiang. They mainly depend on irrigation agriculture for a liveli­hood. Other Turkic minorities in Sinkiang are splinter groups of nationalities living in neighbouring nations of Central Asia, including the Kazakh and Kyrgyz. All these groups are adherents of Islam. The Kazakh and Kyrgyz are pastoral nomadic peoples, still showing traces of tribal organisation. The Kazakh live mainly in north-western and north-eastern Sinkiang as herders, retiring to their camps in the valleys when winter comes; they are established in the 1-li-ha-sa-k'o (Hi Kazakh) Autonomous Prefecture. The Kyrgyz are high-mountain pastoralists and are con­centrated mainly in the westernmost part of Sinkiang.

The Mongolians, who are by nature a nomadic people are the most widely dispersed of the minority nationalities of China. Most of them are inhabitants of the Inner Mon­golia Autonomous Region. Small Mongolian and Mongo­lian-related groups of people are scattered throughout the vast area from Sinkiang through Tsinghai and Kansu and into the provinces of the Northeast (Kirin, Heilungkiang, and Liaoning). In addition to the Inner Mongolia Au­tonomous Region, the Mongolians are established in two autonomous prefectures in Sinkiang, a joint autonomous prefecture with Tibetans and Kazakh in Tsinghai, and several autonomous counties in the western area of the Northeast. Some of them retain their tribal divisions and are pastoralists, but large numbers of Mongolians engage in sedentary agriculture, and some of them combine the growing of crops with herding. The tribes, who are de­pendent upon animal husbandry, travel each year around the pastureland—grazing sheep, goats, horses, cattle, and camels—and then return to their point of departure. A few take up hunting and fur trapping in order to supple­ment their income. The Mongolian language consists of several dialects, but in religion it is a unifying force; most Mongolians are believers in Tibetan Buddhism. A few linguistic minorities in China belong to neither the Sino-Tibetan nor the Altaic language family. The Tajik of westernmost Sinkiang are related to the population of Tajikistan and belong to the Iranian branch of the Indo-European family. The Kawa people of the China-Burma border area belong to the Mon-Khmer branch of the Austro-Asiatic family.

POPULATION GROWTH

Historical records show that, as long ago as 800 вс, in the early years of the Chou dynasty, China was already inhabited by about 13,700,000 people. Until the last years The census of the Hsi (Western) Han dynasty, about ad 2, comparatively accurate and complete registers of population were kept, and the total population in that year was given as 59,600,000. This first Chinese census was intended mainly as a preparatory step toward the levy of a poll tax. Many members of the population, aware that a census might work to their disadvantage, managed to avoid reporting; this explains why all subsequent population figures were unreliable until 1712. In that year the Emperor declared that an increased population would not be subject to tax; population figures thereafter gradually became more accurate.

During the later years of the Pei (Northern) Sung dy­nasty, in the early 12th century, when China was already in the heyday of its economic and cultural development, the total population began to exceed 100,000,000. Later, uninterrupted and large-scale invasions from the north reduced the country's population. When national unifica­tion returned with the advent of the Ming dynasty, the census was at first strictly conducted. The population of China, according to a registration compiled in 1381, was quite close to the one registered in ad 2.

From the 15th century onward, the population increased steadily; this increase was interrupted by wars and natu­ral disasters in the mid-17th century and slowed by the internal strife and foreign invasions in the century that preceded the Communist takeover in 1949. During the 18th century China enjoyed a lengthy period of peace and prosperity, characterized by continual territorial ex­pansion and an accelerating population increase. In 1762 China had a population of more than 200,000.000. and by 1834 the population had doubled. It should be noted that during this period there was no concomitant increase in the amount of cultivable land; from this time on. land hunger became a growing problem. After 1949 sanitation and medical care greatly improved, epidemics were brought under control, and the younger generation became much healthier. Public hygiene also improved, resulting in a death rate that declined faster than the birth rate and a rate of population growth that speeded up again. Population reached 1,000.000.000 in the early 1980s.