This paper investigates the decision-making process of the Ming government during the Sixteenth-century Japanese invasions of Korea (1592- 1598). It argues that the Grand Secretariat, one of the most important institutions within the Ming government, became the other "theatre" of the war. It juxtaposes the chronology of the war with personnel changes within the Grand Secretariat, and argues that Zhao Zhigao, Shi Xing, and Shen Weijing belonged to the "doves" that advocated for peace, whereas Zhang Wei, Shen Yiguan and Xing Jie belonged to the "hawks" that advocated for war.