According to "Azuma Kagami" (The Mirror of the East), Yoshitsune YAMAMOTO was the fifth generation descendant (the fourth generation in family trees) of Shinra-Saburo Yoshimitsu (a brother of MINAMOTO no Yoshiie) living in Omi Province, and the lord of the Yamamotoyama-jo Castle.
『吾妻鏡』によると山本義経は新羅三郎義光（源義家の弟）の5代の跡をつぐ家系（系図類では4代）の近江国住人で、山本山城（滋賀県東浅井郡湖北町）の城主。