The description of Inner Mongolia as a "land of high grasses" implies its pastoral wealth, but much of it has also potential agricultural value. This is particularly true of the fertile zone from the Ala-shan along the alluvial course of the Hwang Ho to the north-east of Kalgan, i.e., along the intermediate belt between the plateau edge and the series of ridges within the Great Wall. The Ordos is a region of stunted steppe vegetation on the whole, but the In-shan series of mountain ridges (i.e., the plateau edge) contains well-watered and sheltered valleys yielding an abundant vegetation.
From very early times the Mongolian Plateau was inhabited by nomadic groups but the term Mongol is comparatively late. It is apparently derived from mong (brave men), the earliest mention of which is in the annals of the Chinese T'ang dynasty (6I8-9o7) where reference is made to the mong-ku invaders. The original homeland of the historic Mongols was the area be tween the Onon and Kerulen rivers south-east of Lake Baikal whence they extended their conquests (see MONGOLS) until their power reached its zenith in the vast empire of Kublai Khan (13th century). The break-up of their empire and the fall of this dynasty (the Yilan) in China were followed by disintegration in Mongolia, where independent communities under separate chiefs came into existence. Soon afterwards the Manchu dynasty was established in China and, following the policy adopted by the Han and T'ang dynasties, set about the task of controlling the critical steppelands of the interior. The Mongol tribes whose lands were adjacent to the northern frontier of China early sub mitted but the more remote Khalka and Kalmuk tribes beyond the Gobi Desert were not brought under control until the reign of K'ang-hsi (1661-1721) or even later. Hence the present distinction between Inner and Outer Mongolia was foreshadowed at this period. In 1689, at the Congress of Dolonor, Mongolia accepted Manchu rule and for more than two centuries the entire area was a dependency of the Manchu Empire. But immediately after the fall of the Manchus in the Revolution of 1911, the northern Mongol princes expelled the Chinese officials at Urga and declared their independence under the rule of the Living Buddha. The political distinction between Outer and Inner Mongolia then finally emerged and corresponds essentially to the natural divisions distinguished on physical grounds. The arid, almost empty wastes of the central Gobi separate the two relatively fertile marginal areas to the north and south which form the cores of Outer and Inner Mongolia respectively, the one orientated towards Siberia, the other towards China. In outlook, in political status, the composition of their populations and in the trend of their economic developments, these two di visions are now quite distinct and the term "Mongolia" used in a political or even in an ethnic sense has now little significance save in relation to the northern republic.
Inner Mongolia comprises a broad belt adjacent to the northern border of China from south Manchuria on the east to Kansu on the west. Its northern boundary against Outer Mon golia runs through the heart of the desert to the great Khingan.
Its eastern boundary with Manchuria extends beyond the Khingan and runs south-eastwards almost to the coast of the Gulf of Liao-tung to include the broken eastern extension of the plateau. The boundary is parallel to the coast for a considerable distance, leaving to Manchuria only a narrow sill traversed by the main route from Peking to Mukden. Opposite Shan-hai-kwan ("the Gate between mountain and sea") it turns west to follow the line of the Great Wall along the scarplands north-west of Peking. Much of this eastern portion of Inner Mongolia, known as Jehol, is drained towards and geographically related to Man churia. From Kalgan the southern boundary follows the outer most scarp along the Great Wall and traverses the Ordos plateau, crossing both arms of the gigantic loop of the Hwang Ho. Finally it runs north-west into the desert, forming in this western section the northern border of the Kansu corridor.
The outstanding features of Inner Mongolia are the progres sive development of Chinese influence and the replacement of nomadism by agriculture and pastoral farming. In the seven teenth century there were few Chinese outside the Great Wall, nor did the early Manchu Emperors encourage emigration. But the Dynasty in its later years, inspired by fear of Japanese pressure from the east and Russian pressure from the north, adopted the Chinese policy of colonization and of direct control of the Mongol tribal organizations through Chinese officials. The establishment of the Republic was followed by a complete political re-organization of Inner Mongolia, bringing it into integral relationship with China proper. With the addition of the portions of the provinces of Chihli and Shansi which lay to the north of the Great Wall there were formed in 1914 the three administrative areas of Jehol, Chahar and Suiyiian (with capital cities at Jehol, Kalgan and Kweihwating respectively) while the semi-desert region of the extreme west was constituted the military district of Sitao and placed under the control of Kansu. Shortly afterwards the Revolution which terminated the Tsarist regime destroyed Russian influence in the south and allowed the policy of active Chinese assimilation to proceed un checked. The process has been carried a stage further by the introduction of the hsien (county) system and the usual ma chinery of provincial administration, and the complete incorpora tion of at any rate Chahar and Suiyiian as provinces of China seems only a question of time. They are included in the northern group, which comprises Hopeh (formerly Chihli) Shansi" and Kansu, at present under the control of Yen Hsi-Shan, the Governor of Shansi. (See under CHINA : Administration.) Jehol is at present in a slightly different category, since it is within the Manchurian sphere. In all essential respects, however, it is becoming as Chinese as Chahar and Suiyilan and this trinity is often known as the "Three North Western Provinces" in contra-distinction to the "Three Eastern Provinces" of Man churia.