It was a period of turmoil between the late 16th century and the early 17th century when Ja-am Lee Min-hwan lived. There were major wars including the Japanese Invasion of Korea in 1592 and the First Manchu Invasion of Korea. King Gwanghae s murder of the Queen Dowager and the enthronement of the new king Injo shook the political world upside down. When Later Jin conquered the Fushun area in 1618, the Ming Dynasty asked Chosun to send reinforcements to drive Later Jin out of the area. King Gwanghae refused to dispatch the Chosun troops citing many different realistic reasons. But after a series of Ming s further requests and the high officials appeals to support the dispatch, Chosun finally gave in and sent the troops. However, King Gwanghae didn t change his position against the dispatch to the end. The Chosun troops arrived in Liaodong only to be defeated in the Simha battle and become war prisoners 15 days after they crossed River Aprok. Following Kang Hong-rip as one of his men to the war, Lee Min-hwan recorded everything that took place for about 17 months from the early days of dispatch to the first skirmish, Simha battle and being captured after losing the battle. Published in his Ja-amjip, the Chaekjungilok is the war journal and Chaekjung report of the Chosun troops dispatched to Liaodong. His Jaamjip also describes the international politics in the 17th century very vividly and serves as valuable historical data to illuminate the political situation under the reign of King Gwanghae in the middle Chosun and the positions and trends of Chosun, Ming, and Later Jin. Jaamjip contains very important data not only about the political situation under the reign of King Gwanghae in the middle Chosun, but also about the subtle dynamics of international relations during those days, which makes Jaamjip a personal journal and social heritage of the days at the same time. Especially Lee was forced to leave the office often being caught in the middle of party strife. He was a loyal servant that was worried about the invasion of foreign forces and made an official suggestion to reinforce the guards along the northern border. He was also a public official devoted to saving people who were starving after a bad harvest year after year. In his old days, he was an active writer. Some of the books introduced in the paper have not been discovered yet but surely deserve future efforts to find and study them.