Yagyū Jūbei Mitsuyoshi(born "Shichirō") grew up in his family's ancestral lands, Yagyū no Sato, now in Nara. He was the son of Yagyū Tajima no Kami Munenori, master swordsman of the Tokugawa Shoguns, especially Ieyasu and Tokugawa Iemitsu, who prized Munenori as one of his top councillors. Munenori fought for the first Tokugawa shogun, Tokugawa Ieyasu, at the Battle of Sekigahara, expanding the Shogun's territory. For his efforts, Munemori was made the Shogun's sword instructor and a minor daimyo or provincial ruler. Munenori would go on to train three successive Shoguns: Ieyasu, Hidetada, and Iemitsu.

Source - Wikipedia