The Joseon Dynasty in South Korea was established at the end of the 14th century and lasted until the beginning of the 20th century. During these more than 500 years, it remained unified under the rule of 27 kings, which is unprecedented in historical records. Each king was assigned a royal minister whose duty was to record the king's diary. After the king died, the historians in the palace compiled these records and left them to future generations and the next king. These diaries are called "Royal Records of the Joseon Dynasty." It was preserved intact. The King of Yanshan in this historical record was a famous tyrant, and his cruelty was unparalleled. Nevertheless, this record also allows us to see a man of temperament. When he was a child, his mother was murdered by a conspiracy in the palace and died of poisoned wine. Her death left a permanent mental scar on the future monarch, which was undoubtedly the main cause of his twisted character. On September 2, 1506, he was deposed from the throne due to a riot caused by the nobles.