This is a study of the creation of a heroic war myth – that of “Military God Commander Hirose” – by the Japanese Ministry of Navy during the Russo-Japanese war. The process of myth-making was a highly systematic one, spearheaded by a naval historian, Ogasawara Naganari. At the time of its creation, the Hirose myth symbolised the new moral standard that the Navy had wanted to disseminate by focusing on the fraternal relationship between officers and subordinates. Reasons for the choice of Hirose as the suitable material for a heroic myth will be examined. It will be argued that, to an extent, the choice of Hirose represented the aspirations of the Navy’s own self-image, which was also reflected in the internationalist aspirations of Japan as a new great power.