In 383 came the great assault of the Tibetan Fu Chien against
the south. As we know, the defence was carried out more by the methods of diplomacy and intrigue than by military means, and it led to the disaster in the north already described. The successes of the southern state especially strengthened the Hsieh family, whose generals had come to the fore. The emperor (Hsiao Wu Ti, 373-396), who had come to the throne as a child, played no part in events at any time during his reign. He occupied himself occasionally with Buddhism, and otherwise only with women and wine. He was followed by his five-year-old son. At this time there were some changes in the court clique. In the Huan family Huan Hsüan, a son of Huan Wen, came especially into prominence. He parted from the Hsieh family, which had been closest to the emperor, and united with the Wang (the empress's) and Yin families. The Wang, an old Shansi family, had already provided two empresses, and was therefore strongly represented at court. The Yin had worked at first with the Hsieh, especially as the two families came from the same region, but afterwards the Yin went over to Huan Hsüan. At first this new clique had success, but later one of its generals, Liu Lao-chih, went over to the Hsieh clique, and its power declined. Wang Kung was killed, and Yin Chung-k'an fell away from Huan Hsüan and was killed by him in 399. Huan Hsüan himself, however, held his own in the regions loyal to him. Liu Lao-chih had originally belonged to the Hsieh clique, and his family came from a region not far from that of the Hsieh. He was very ambitious, however, and always took the side which seemed most to his own interest. For a time he joined Huan Hsüan; then he went over to the Hsieh, and finally returned to Huan Hsüan in 402 when the latter reached the height of his power. At that moment Liu Lao-chih was responsible for the defence of the capital from Huan Hsüan, but instead he passed over to him. Thus Huan Hsüan conquered the capital, deposed the emperor, and began a dynasty of his own. Then came the reaction, led by an earlier subordinate of Liu Lao-chih, Liu Yü. It may be assumed that these two army commanders were in some way related, though the two branches of their family must have been long separated. Liu Yü had distinguished himself especially in the suppression of a great popular rising which, around the year 400, had brought wide stretches of Chinese territory under the rebels' power, beginning with the southern coast. This rising was the first in the south. It was led by members of a secret society which was a direct continuation of the "Yellow Turbans" of the latter part of the second century A.D. and of organized church-Taoism. The whole course of this rising of the exploited and ill-treated lower classes was very similar to that of the popular rising of the "Yellow Turbans". The movement
spread as far as the neighbourhood of Canton, but in the end it was suppressed, mainly by Liu Yü.
Through these achievements Liu Yü's military power and political influence steadily increased; he became the exponent of all the cliques working against the Huan clique. He arranged for his supporters to dispose of Huan Hsüan's chief collaborators; and then, in 404, he himself marched on the capital. Huan Hsüan had to flee, and in his flight he was killed in the upper Yangtze region. The emperor was restored to his throne, but he had as little to say as ever, for the real power was Liu Yü's.
Before making himself emperor, Liu Yü began his great northern campaign, aimed at the conquest of the whole of western China. The Toba had promised to remain neutral, and in 415 he was able to conquer the "Later Ch'in" in Shensi. The first aim of this campaign was to make more accessible the trade routes to Central Asia, which up to now had led through the difficult mountain passes of Szechwan; to this end treaties of alliance had been concluded with the states in Kansu against the "Later Ch'in". In the second place, this war was intended to increase Liu Yü's military strength to such an extent that the imperial crown would be assured to him; and finally he hoped to cut the claws of pro-Huan Hsüan elements in the "Later Ch'in" kingdom who, for the sake of the link with Turkestan, had designs on Szechwan.
3 The Liu-Sung dynasty (A.D. 420-478) and the Southern Ch'i dynasty (479-501)
After his successes in 416-17 in Shensi, Liu Yü returned to the capital, and shortly after he lost the chief fruits of his victory to Ho-lien P'o-p'o, the Hun ruler in the north, while Liu Yü himself was occupied with the killing of the emperor (419) and the installation of a puppet. In 420 the puppet had to abdicate and Liu Yü became emperor. He called his dynasty the Sung dynasty, but to distinguish it from another and more famous Sung dynasty of later time his dynasty is also called the Liu-Sung dynasty.
The struggles and intrigues of cliques against each other continued as before. We shall pass quickly over this period after a glance at the nature of these internal struggles.
Part of the old imperial family and its following fled northwards from Liu Yü and surrendered to the Toba. There they agitated for a campaign of vengeance against South China, and they were supported at the court of the Toba by many families of the gentry with landed interests in the south. Thus long-continued fighting started between Sung and Toba, concerned mainly with the
domains of the deposed imperial family and its following. This fighting brought little success to south China, and about 450 it produced among the Toba an economic and social crisis that brought the wars to a temporary close. In this pause the Sung turned to the extreme south, and tried to gain influence there and in Annam. The merchant class and the gentry families of the capital who were allied with it were those chiefly interested in this expansion.