1223 A.D. marks the beginning of that long series of depredations which Japanese freebooters inflicted upon Koryŭ between 1200 and 1400. In this year they landed on the coast of Kyŭng-sang Province and ravaged the district of Keum-ju. With the opening of the next year, a Mongol envoy came modifying the demand for tribute to sea otter skins only. The Kin dynasty was now tottering to its fall but was destined to cling to life for another ten years. This year saw it nearly fall before the Mongol power. Koryŭ therefore discarded the Kin calendar. The friendship between the Mongols and Koryŭ was destined to be rudely broken in the year 1225, and through no fault of the latter except the inability to keep order in her own territory. The Mongol envoy, returning to the north, was set upon by a Koryŭ highwayman and was robbed of the gifts which he was carrying home. Thus all friendly relations were ruptured and another step was taken toward the final catastrophe. This year also witnessed another Japanese raid in the south. [Illustration: _FERRY ACROSS THE HAN._] The Yŭ-jin who had now assumed the Mongol clothes, and were in reality an integral part of the Mongol power, made a descent upon Koryŭ in 1226 in the vicinity of Eui-ju. The prefect deemed it too pressing a matter to wait till word could be received from Song-do, so he sent a thousand men immediately against the raiders and drove them back. The king forgave the irregularity but refused to reward him. Ch‘oé U who, as we know, was the prime minister, was duped by a diviner into believing that he was to become king some day, and he foolishly divulged the secret to a certain Kim, and soon it became common property. As punishment for this, as well as to get himself out of trouble, Ch‘oe U had both Kim and the diviner drowned. The depredations of the Japanese were without the cognizance of the Japanese government and were against its wish. This appears from the fact that when in 1227 an envoy, Pak In, was sent to Japan to remonstrate against them, the government of that country acquiesced and arrested and killed a number of the corsairs. Both this year and the next Yŭ-jin bands ravaged the northern part of Koryŭ, but at the same time asked that a treaty be concluded. The ink was hardly dry on this before it was broken by the very ones who advocated it.