Shinkage Ryū Kiriai Kuden-sho no Koto
Sekishūsai gathered the oral teachings of Kamiizumi Ise-no-kami, systematized them, and set them down in the “Shinkage Ryū Kiriai Kuden-sho no Koto”. He gave this text to his grandchild, Yagyū Hyōgonosuke Toshitoshi, in 1603.
This text concretely outlines Kamiizumi Ise-no-kami’s approach to heihō, the martial arts, and the art of swordsmanship.

Sekishūsai was given an inka, a certificate of mastery, in April 1565 and was named the legitimate second headmaster. In May of 1566, he was then given the four scrolls of the Kagemokuroku: Enpi, Sangaku, Kuka, and Nanatachi.

“Motsujimi Shudan Kuden-sho” by Yagyū Munetoshi

Motsujimi Shudan Kuden-sho
In August of 1604, when he finished writing the Motsujimi Shudan Kuden-sho (A Mind Without Strife or Selfishness), Sekishūsai appointed Toshitoshi as his successor. Sekishūsai added three more important items to the Motsujimi Shudan Kuden-sho before Toshitoshi inherited the position in June 1605 and became the third headmaster. At that time, Sekishūsai gave the Motujimi Shudan Kuden-sho to Toshitoshi along with two other scrolls: the Shinkage Ryū Heihō Mokuroku no Koto, and the Shinkage Ryū Kiriai Kuden-sho no Koto. Sekishūsai was 77 and Toshitoshi was 28 years old.

Founder of Owari Yagyū, Yagyū Hyōgonosuke Toshitoshi

Shijū Fuja-sho
Owari Gondainagon Tokugawa Yoshinao, the first head of the Owari Tokugawa domain, became the fourth headmaster of Shinkage Ryū in 1620. At that time, the third headmaster, Yagyū Hyōgonosuke Toshitoshi, presented him with the Shijū Fuja-sho along with the other catalogues of techniques and teachings.
In the Shijū Fuja-sho, Toshitoshi describes heihō for armored combat. This heihō is characterized by low stances, and it was this style that the founder of Shinkage Ryū, Kamiizumi Ise-no-kami, taught to Sekishūsai. In this revolutionary text, Toshitoshi also introduces principles he devised for fighting without armor,as befitting the new era after the Genna Armistice.
While it could be said that the transition from the low stances of armored combat to the erect and unencumbered postures of combat in everyday clothing was inevitable, this was certainly a great achievement for Toshitoshi in the history of Japanese swordsmanship.

The 5th headmaster, the 5th family head, Yagyū Renya Toshikane

Shinkage Ryū Heihō Mokuroku (Renya kuden-sho)
The Shinkage Ryū Heihō Mokuroku is a collection of teachings thought to have been written by the fifth headmaster, Yagyū Renya Toshikane, when he was 12 or 13 years old. He briefly summarizes the concepts taught by the founder of the school, Kamiizumi Ise-no-kami, and the second headmaster, Yagyū Sekishūsai, and provides comments on each item in the four scrolls. He discusses the technique and theory of each in terms of the “old” theory of the first and second headmasters and in terms of the “current” theory of his father, Toshitoshi. Renya sealed this text and never showed it to other people. He then passed it down to his nephew, the eighth headmaster, after writing on the cover that anyone who broke the seal, would face punishment by Marishiten, a Buddhist deity. It is taught that the eleventh headmaster, Yagyū Toshiharu, gathered his extraordinary courage and conviction and opened the scroll, and it has illuminated the understanding of successive headmasters ever since.