In 108 B.C. the western part of Korea was also conquered. Korea was already an important transit region for the trade with Japan. Thus this trade also came under the direct influence of the Chinese government. Although this conquest represented a peril to the eastern flank of the Hsiung-nu, it did not by any means mean that they were conquered. The Hsiung-nu while weakened evaded the Chinese pressure, but in 104 B.C. and again in 91 they inflicted defeats on the Chinese. The Hsiung-nu were indirectly threatened by Chinese foreign policy, for the Chinese concluded an alliance with old enemies of the Hsiung-nu, the Wu-sun, in the north of the Tarim basin. This made the Tarim basin secure for the Chinese, and threatened the Hsiung-nu with a new danger in their rear. Finally the Chinese did all they could through intrigue, espionage, and sabotage to promote disunity and disorder within the Hsiung-nu, though it cannot be seen from the Chinese accounts how far the Chinese were responsible for the actual conflicts and the continual changes of _shan-yü_. Hostilities against the Hsiung-nu continued incessantly, after the death of Wu Ti, under his successor, so that the Hsiung-nu were further weakened. In consequence of this it was possible to rouse against them other tribes who until then had been dependent on them--the Ting-ling in the north and the Wu-huan in the east. The internal difficulties of the Hsiung-nu increased further. Wu Ti's active policy had not been directed only against the Hsiung-nu. After heavy fighting he brought southern China, with the region round Canton, and the south-eastern coast, firmly under Chinese dominion--in this case again on account of trade interests. No doubt there were already considerable colonies of foreign merchants in Canton and other coastal towns, trading in Indian and Middle East goods. The traders seem often to have been Sogdians. The southern wars gave Wu Ti the control of the revenues from this commerce. He tried several times to advance through Yünnan in order to secure a better land route to India, but these attempts failed. Nevertheless, Chinese influence became stronger in the south-west. In spite of his long rule, Wu Ti did not leave an adult heir, as the crown prince was executed, with many other persons, shortly before Wu Ti's death. The crown prince had been implicated in an alleged attempt by a large group of people to remove the emperor by various sorts of magic. It is difficult to determine today what lay behind this affair; probably it was a struggle between two cliques of the gentry. Thus a regency council had to be set up for the young heir to the throne; it included a member of a Hsiung-nu tribe. The actual government was in the hands of a general and his clique until the death of the heir to the throne, and at the beginning of his successor's reign.