, meaning "one-sword school", is the ancestor school of several

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the n ...

ese Koryū

kenjutsu is an umbrella term for all ('' ko-budō'') schools of Japanese swordsmanship, in particular those that predate the Meiji Restoration. Some modern styles of kendo and iaido that were established in the 20th century also included modern forms ...

styles, including Ono-ha, Mizoguchi-ha, Nakanishi-ha, Kogen, Hokushin, and Itto Shoden. The style was developed by Itō Ittōsai Kagehisa.

Ono-ha Ittō-ryū

is the oldest of the many Ittō-ryū styles which branched off from Ittōsai Kagehisa's original art. 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 is a modern Japanese martial art, descended from kenjutsu (one of the old Japanese martial arts, swordsmanship), that uses bamboo swords ( shinai) as well as protective armor ( bōgu). Today, it is widely practiced within Japan and has spre ...

kata ''Kata'' is a Japanese word ( 型 or 形) meaning "form". It refers to a detailed choreographed pattern of martial arts movements made to be practised alone. It can also be reviewed within groups and in unison when training. It is practise ...

, 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. Serving as an instructor to both the second and third ''

shōgun , officially , was the title of the military dictators of Japan during most of the period spanning from 1185 to 1868. Nominally appointed by the Emperor, shoguns were usually the de facto rulers of the country, though during part of the Kamaku ...

s'', along with

Yagyū Munenori was a Japanese daimyo, swordsman, and martial arts writer, founder of the Edo branch of Yagyū Shinkage-ryū, which he learned from his father Yagyū "Sekishūsai" Muneyoshi. This was one of two official sword styles patronized by the Tokugaw ...

of the rival school the Yagyū Shinkage-ryū, Tadaaki was able to continue to give his art wide exposure. It was said that Tadaaki was Munenori's superior in swordsmanship, but that his severe character led him to be the less favoured and respected of the two. Known as a

duel A duel is an arranged engagement in combat between two people, with matched weapons, in accordance with agreed-upon rules. During the 17th and 18th centuries (and earlier), duels were mostly single combats fought with swords (the rapier and ...

ing style which focused upon the sword rather than a more multifaceted, multi-weapon, battlefield style, Ono developed a mock sword (see: shinai) in order to reduce training injuries and allow more committed fighting practice. From a technical standpoint this style consists of more than 150 techniques for both

long Long may refer to: Measurement * Long, characteristic of something of great duration * Long, characteristic of something of great length * Longitude (abbreviation: long.), a geographic coordinate * Longa (music), note value in early music mensu ...

and

short swords The English language terminology used in the classification of swords is imprecise and has varied widely over time. There is no historical dictionary for the universal names, classification or terminology of swords; a sword was simply a double ...

. ''Kiri-otoshi'', which translates simply as "cutting down", is still the defining technique, like that of its parent style. Characteristically, practitioners often feel that they have the ability to strike freely due to their technique of cutting down the centre-line during an opponent's cut in order to displace their attacker's sword and gain victory. The style adheres to a philosophy articulated in the phrase "" or "one sword gives rise to ten thousand swords," meaning that a thorough understanding of the fundamental technique of cutting will lead one to understand the myriad variations. Although formally established as a system for unarmoured fighting, the techniques maintained an awareness of the demands and tactics of armoured fighting, making the techniques adaptable to such circumstances. The transmission of the system passed out of the Ono family briefly and was maintained by the feudal lord

Tsugaru Nobumasa was the 4th ''daimyō'' of Hirosaki Domain in northern Mutsu Province, Honshū, Japan (modern-day Aomori Prefecture). His courtesy title was '' Etchū-no-kami,'' and his Court rank was Junior Fifth Rank, Lower Grade. Biography Tsugaru Nobumasa ...

. The second headmaster from this family taught Ono Tadakata, allowing the Ono family to continue preserving the line while the Tsugaru family continued their practice of the art, thereby having two families maintain the main line of the Ono-ha Ittō-ryū tradition thereafter. The Tsugaru family also taught the system to members of Yamaga family, and they worked together to preserve the line of their art. Sasamori Junzo, a well known and high ranking kendo practitioner, took over the preservation of the system in the Taishō period and his son, Sasamori Takemi, succeeded him as the 16th headmaster of the system.

Mizoguchi-ha Ittō-ryū

was founded by Mizoguchi Shingoemon Masakatsu, who was a student of the second headmaster of Ono-ha Ittō-ryū, Ono Jiroemon Tadatsune, before creating his own style, the Mizoguchi-ha. Ito Masamori, a student of Mizoguchi's, visited the

Aizu is the westernmost of the three regions of Fukushima Prefecture, Japan, the other two regions being Nakadōri in the central area of the prefecture and Hamadōri in the east. As of October 1, 2010, it had a population of 291,838. The princi ...

clan and taught Edamatsu Kimitada an incomplete version of the art. Ikegami Jozaemon Yasumichi, a student of Edamatsu, was sent by the ''

daimyō were powerful Japanese magnates, feudal lords who, from the 10th century to the early Meiji period in the middle 19th century, ruled most of Japan from their vast, hereditary land holdings. They were subordinate to the shogun and nominall ...

'' (feudal lord) to study the sword methods to be found in

Edo Edo ( ja, , , "bay-entrance" or "estuary"), also romanized as Jedo, Yedo or Yeddo, is the former name of Tokyo. Edo, formerly a ''jōkamachi'' (castle town) centered on Edo Castle located in Musashi Province, became the ''de facto'' capital of ...

(present-day

Tokyo Tokyo (; ja, 東京, , ), officially the Tokyo Metropolis ( ja, 東京都, label=none, ), is the capital and largest city of Japan. Formerly known as Edo, its metropolitan area () is the most populous in the world, with an estimated 37.46 ...

). Combining methods learned there with the original teachings of Mizoguchi-ha Ittō-ryū, he created a distinct Aizu line of the Mizoguchi-ha school with many significant differences in technique. This is the line that survives today, as the original line has disappeared. Watching a demonstration of the Mizoguchi-ha Ittō-ryū it easily distinguishable from its parent art, the Ono-ha Ittō-ryū, and the Nakanishi-ha and Itto Shoden Muto-ryū. The kata used in these styles bear a close resemblance to each other. The Mizoguchi-ha at times looks like an entirely different art rather than just a different branch of the Ittō school, although employing some similar tactics. Many of the kata seem more overtly instructive in their orientation, teaching tactics to the left and then to the right. The curriculum consists of five long-sword and three short-sword techniques with ''omote'' (outside/surface) and ''ura'' (inner/more sophisticated) versions. Being a traditional school of the Aizu clan, which was based in Fukushima, it is currently maintained by the Fukushima prefecture and local kendo federations. There is also a group of practitioners in Kōbukan kendo club (Nakano, Tokyo) lead by Hiroshi Ozawa sensei that regularly demonstrates Mizoguchi-ha Ittō-ryū at annual Kyoto Enbu Taikai.2016 Kyoto Enbu Taikai Match Schedule
/ref> 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.

Nakanishi-ha Ittō-ryū

was founded by Nakanishi Chuta Tanesada who studied under either the 5th or 6th generation headmaster of Ono-ha Ittō-ryū, before establishing his own style. His son revolutionized practice by implementing the use of shinai, a bamboo mock sword, in conjunction with

bōgu , properly called , is training armour used primarily in the Japanese martial art of kendo,Uchida, M. (2005)Kendo Bogu (Protective Equipment)(October 2005). Retrieved on 12 May 2010.

, a protective armor. (Shinai were already used in Shinkage-ryū, Nen-ryū, and Tatsumi-ryū by this time.) 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. Stylistically the Nakanishi branch is said to more closely resemble its source, the Ono-ha Ittō-ryū, than do any other branches of the Ittō-ryū. The kata practiced on the surface appear to be identical in form but differ in such aspects as timing, breathing, and use of distance. The Nakashima branch is marked by its wide stances and deliberate movements, which confer a feeling of power and dignity. 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. Many famous swordsmen have emerged from this ryū, some founding schools of their own. Some of the more prominent among them were: * Terada Gouemon (Founder of the Tenshin Ittō-ryū) * Shirai Toru (Successor to Terada) * Takayanagi Yoshimasa (Founder of the Takayanagi-ha Toda-ryū) * Asari Yoshinobu (Teacher to Yamaoka Tesshu) * Chiba Shūsaku (Founder of

Hokushin Ittō-ryū Hokushin Ittō-ryū Hyōhō (北辰一刀流兵法) is a koryū (古流) that was founded in the late Edo period (1820s) by Chiba Shusaku Narimasa (千葉周作成政, 1794–1856). He was one of the last masters who was called a Kensei (swor ...

) * Takano Sazaburo (A key developer of modern swordsmanship). 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.

Kogen Ittō-ryū

was founded by Henmi Tashiro Yoshitoshi, a student of Sakurai Gosuke Nagamase, who in turn was an exponent of the Aizu branch of Mizoguchi-ha Ittō-ryū. The Henmi dojo still stands in Saitama Prefecture. This is Ryūnosuke Tsukue's sword school in the 1966 historical drama

The Sword of Doom ''The Sword of Doom'', known in Japan as , is a 1966 Japanese ''jidaigeki'' film directed by Kihachi Okamoto and starring Tatsuya Nakadai. It is based on the serial novel of the same title by Kaizan Nakazato. Plot The story follows the life of Ryu ...

(大菩薩峠).

Tatsuya Nakadai is a Japanese film actor. He was featured in 11 films directed by Masaki Kobayashi, including '' The Human Condition'' trilogy, wherein he starred as the lead character Kaji, plus ''Harakiri'', '' Samurai Rebellion'' and '' Kwaidan''. Nakadai ...

played the part of Ryūnosuke in this film.

Hokushin Ittō-ryū

(北辰一刀流) was founded in the late Edo period (1820s) by Chiba Shūsaku Narimasa (1794–1856). He was one of the last masters who was called a Kensei (sword saint).

Ittō Shōden Mutō-ryū

was founded by Yamaoka Tetsutaro Takayuki, better known as

Yamaoka Tesshū , also known as Ono Tetsutarō or Yamaoka Tetsutarō, was a famous samurai of the Bakumatsu period, who played an important role in the Meiji Restoration. He is also noted as the founder of the '' Itto Shoden Muto-ryu'' school of swordsmanship. ...

, an exponent of Ono-ha Ittō-ryū, Nakanishi-ha Ittō-ryū and Hokushin Ittō-ryū, in which he received a license of full transmission.

Tadanari-ha Ittō-ryū

Tadanari-ha (Chuya-ha) Ittō-ryū (忠也派一刀流) was founded by Itō Tenzen Tadanari.

Tenshin Ittō-ryū

Tenshin Ittō-ryū (天辰一刀流) was founded by Suzuki Naonoshin Akemitsu. He learned Yagyu-Shingan-ryu (柳生心眼流), Ono-ha Ittō-ryū (小野派一刀流) in Sendai-Han, and learned Hokushin Ittō-ryū (北辰一刀流) in Edo (1840). In 1857, he was appointed the kenjutsu teacher of the Sendai-han. Then, he founded Tenshin Ittō-ryū (天辰一刀流) from the 3 schools. The school still stands in Sendai, Miyagi.