Colonel Eikiichi Matsudaira was an officer in the Yamatian military and brother of Takeshi Matsudaira. He took Remy Aurelac, who was disguised as a Scunnish major, into his regiment during the Yamatian Invasion of Aison, unaware of Remy's true identity. Eikiichi was also blissfully unaware of how stupid Scuns were, and Remy used his ignorance to his advantage later on. During the Great War, Eikiichi was tasked with defending Myridia and ultimately perished when the Grand Alliance's army took over the city in the Second Battle of Myridia.