It continues to be one of the most influential of the traditional kenjutsu styles today, exerting a major influence, along with Hokushin branch, upon modern kendo's kata, tactics, and aesthetic.
Ono-ha was founded by Ittōsai's immediate successor, Mikogami Tenzen (also known as Ono Jiroemon Tadaaki, 1565–1628), from whence the name of the art is derived.
Oral tradition indicates that Ittosai made Tadaaki fight a serious duel with another student, Zenki, in order to establish a successor to the style.
Ito Masamori, a student of Mizoguchi's, visited the Aizu clan and taught Edamatsu Kimitada an incomplete version of the art.
Ikegami Jozaemon Yasumichi, a student of Edamatsu, was sent by the daimyō (feudal lord) to study the sword methods to be found in Edo (present-day Tokyo).
There is also a group of practitioners in Kōbukan kendo club (Nakano, Tokyo) led by Hiroshi Ozawa sensei[2] that regularly demonstrates Mizoguchi-ha Ittō-ryū at annual Kyoto Enbu Taikai.
[3] Although Takeda Sōkaku, the founder of Daitō-ryū, claimed to maintain the traditional teachings of the Aizu clan, according to his son, Tokimune, the core of his approach to the sword, although modified, was based upon the Ono-ha Ittō-ryū rather than Mizoguchi-ha.
His son revolutionized practice by implementing the use of shinai, a bamboo mock sword, in conjunction with bōgu, a protective armor.
Using the equipment to allow swordsmen to practice techniques freely and engage in sporting matches, foreshadowing the rise of modern kendo, led to the rapid popularity of the Nakanishi branch of Ittō-ryū.
This style, like the Ono-ha Ittō-ryū, employs the use of the heavily padded glove known as the "onigote," to allow forceful finishing strikes practiced as the denouement of each kata.
Some of the more prominent among them were: Takano, as a well known educator, was able to introduce swordsmanship into the public school system in Japan and was instrumental to the development of the Nihon Kendo Kata.