From Seiwa to Minamoto
Tradition tells us that in Emperor Seiwa’s days and even more so during the reign of his sixth son, Sadazumi, warriors used their bare hands to strike parts of the body that were either only poorly protected or even unprotected by their armor with blows that were similar to sword strikes. To this day, such techniques are a characteristic element of Aikido in the Takeda style, for example the Aiki Uchi (also known as Tegatana Uchi, the aiki method of striking).
Passed on by Sadazumi, this Knowledge was transmitted by his son Tsunemoto, the ancestor of the Seiwa Genji (Minamoto dynasty), to Minamoto (no) Mitsunaka, then to Minamoto (no) Yorinobu and by him to Minamoto (no) Yoriyoshi, father of the Yoshimitsu, and eventually to the famous general Yoshimitsu.
Under Yoshimitsu of the powerful Minamoto family, which founded the mighty Kamakura shogunate in 1192, the traditional aiki techniques were further improved upon and developed into a system for the first time.