During the Edo Shogunate period, relations between the Joseon Dynasty and Japan were good. This was because the Edo Shogunate had interacted with the Joseon Dynasty in a low profile due to the cleanup of the exodus by Toyotomi Hideyoshi. However, the attitude of the Joseon Dynasty toward Japan continued to deteriorate after the start of the Meiji period. The reason for this is that Yi Joseon had been an isolationist nation and had established the Qing Dynasty (China ) as its suzerain state. What particularly infuriated Yi Joseon was the fact that "imperial "and "emperor" were written in diplomatic documents. The Meiji government's idea was to ally with Korea and modernize together as a defensive measure against Romanov Dynasty Russia, which was a threat at the time. However, the hardening attitude of Yi Joseon led them to consider opening the country by force. This is the "conquest of Korea theory ". The most active in this argument were Eto Shinpei and Itagaki Taisuke. It was decided to dispatch Saigo Takamori, the most influential person in the government, as the emissary, but Iwakura and Okubo, who had returned from overseas, vehemently opposed the decision. In the middle of this confusion, Sanjo Sanetomi, the Grand Minister of State at the time, died of illness, and the matter was finally left to the Imperial Council, which included the Emperor Meiji. In the end, Saigo's dispatch was canceled, and Saigo, Eto, Itagaki, and the others left the government, taking responsibility for the confusion. This was the "Political Incident of 1873.
Thus, the former government officials who had gone into the field were forced to rebel with the disgruntled samurai in their native lands. 「The Seinan Civil War 」was the largest of rebels, and the last civil war in Japanese history. While this tragedy enhanced the practical capabilities of the Japanese military, it also instilled in them the idea that they should lay down their lives for the sake of their country.
