In 1265 the seed was sown that led to the attempted invasion of Japan by the Mongols. A Koryŭ citizen, Cho I, found his way to Peking and there, having gained the ear of the emperor, told him that the Mongol power ought to secure the vassalage of Japan. The emperor listened favorable and determined to make advances in that direction. He therefore appointed Heuk Chŭk and Eun Hong as envoys to Japan and ordered them to go by way of Koryŭ and take with them to Japan a Koryŭ envoy as well. Arriving in Koryŭ they delivered this message to the king and two officials, Son Kun-bi and Kim Ch‘an were appointed to accompany them to Japan. They proceeded by the way of Kö-je Harbor in Kyŭng-sang Province but were driven back by a fierce storm and the king sent the Mongol envoys back to Peking. The Emperor was ill satisfied with the outcome of the adventure and sent Heuk Chŭk with a letter to the king ordering him to forward the Mongol envoy to Japan. The message which he was to deliver to the ruler of Japan said “The Mongol power is kindly disposed toward you and desires to open friendly intercourse with you. She does not desire your submission but if you accept her patronage the great Mongol empire will cover the earth.” The king forwarded the message with the envoys to Japan, and informed the emperor of the fact. Meanwhile the emperor was being worked upon by designing men who were seeking to injure Koryŭ. They succeeded so well in their designs that he sent an envoy bearing a list of specified charges against the king. (1) You have enticed Mongol people to Koryŭ. (2) You did not feed our troops when they were in Koryŭ. (3) You persistently refuse to come back to the capital. (4) When our envoy went to Koryŭ you had a spy watch him. (5) Your tribute has not been at all equal to the demand we made. (6) You brought it about that the Japanese did not accept our offer. The emperor’s suspicions continued to increase until finally he sent a general, U-ya Son-dal, to demand that Yi Chang-yong and Kim Chun, two of the most influential officials of Koryŭ, together with the father and son of the latter, be brought to Peking. Kim Chun, on learning of this, advised that the envoy be promptly killed and that the king remain in some island, out of harm’s way. But the king knew that such a course would be suicidal and firmly refused. So Kim Chun himself put Gen. U-ya Son-dal to death and then announced the fact to the court. The king and court were dumbfounded at his temerity but dared not lay hands on him, though they all felt sure they would suffer for his rash act. Fortunately for them, however, other events of great importance were happening which distracted the attention of the emperor and secured immunity from punishment. These events we must now relate.