Taisha Ryu is a Japanese system that was at one time famous for guarding the Shogun in Edo castle. However, few know the history of the Ryu and its association with ninjutsu. The group they were associated with were the Sagara ninja that served as a "secret service" group for the Shogun. They eventually became feared by all of the other warlords and developed a special technique called the Ura dachi or inner sword.
The founder of the Taisha Ryu was a one Marume Kurando (1540-1629) who was also known as Marume Ishimi no Kami Nyudo Tessai Fujiwara Nagayoshi Kurando no Suke (now you see why his name was abbreviated). Marume Kurando was said to be a master with the sword from a very early age. It is said that he had his first match at the ripe age of 16, after which he studied Hyoho (military strategy) in Amakusa for about two years. He later entered the Shinkage Ryu of kenjutsu (swordsmanship) at the age of 19. This Shinkage Ryu ("new") was a branch of the older Kage Ryu and was formed after adding Zen buddhism. Marume Kurando orginally had heard of the famous teacher in Kyoto named Kami Izumi Isenokami Nobutsuna and wanted to test his skills with this swordsman. Kurando travelled there and after being badly beaten he immediately asked to become he disciple. Kurando studied kenjutsu very hard for about 5 years and eventually obtained menkyo kaiden (license of complete transmission) in 1567. After returning home, Kurando continued his training and added Marishiten no Ho from India (essentially Mikkyo), and an ancient theory of Izanagi Izanami no Ho to create a new school. This school was later named Shinkage Taisha Ryu. After incorporating these aspects he considered his new school to be a Sogo bujutsu (all encompassing). Eventually, the Shinkage was dropped and the Ryu only went by Taisha and the its main teaching became Ura Dachi. At this point, Marume Kurando had a new Ryu and wanted it to be seen by his original teacher so an embu (demonstration) was prepared. Kurando demonstrated the kata with Nobutsuna Ise no Kami in front of the Shogun Ashikaga Teruyoshi (ca. 1565). The Shogun was very impressed with this embu and gave him a letter which stated that the "Under Heaven the Hyoho (military strategy) of Kami Izumi, is the best ever and should be treated as a treasure." This embu and letter gave immediate respect for his new found ryuha.
Marume Kurando again returned home and served under the warlord Sagara Yoshiaki. Kurando didn't do so well and lost a decisive battle and as a result was cast aside for approximately 15 years. During this time Kurando refined his budo and formed the Sagara ninja group. Kurando eventually became Shinan yaku (top sword teacher) for the new leader of the Sagara han, Sagara Nagatsune. While Kurando taught kenjutsu (swordsmanship) to all of the warriors in this group he also continued to develop the network of espionage agents. At this time Kurando employed a good friend of his from China named Denribo. It is thought that Denribo was originally a pirate and had traveled frequently getting to know hoards of people, which enhanced his involvement with Kurando's group. Denribo became an excellent addition to his group and added many positive aspects. Denribo was excellent at networking with other groups. He is the one responsible for obtaining a variety of Shugenja (mountain ascetics) to aide the Sanada ninja group in intelligence gathering.
These Sagara ninja groups were used heavily against smuggling in the sea. There was said to be at least 10 different groups with all of them being headed by a menkyo kaiden in Taisha Ryu. Interestingly, the groups had titles based upon the names of sword techniques from the Ryu. They were all directly under the supervision of Kurando Marume and had at up to 24 chunin (middle level operatives) and about 16 Genin (lower level operatives). The Chunin were the ones that took orders and dispatched the Genin on a variety of espionage assignments. All of the Chunin were said to be skilled in many areas of bujutsu and always displayed deep insight and personalities. These groups were used to guard many famous people and said to have actually foiled other ninja groups in their assassination attempts.
Marume Kurando, the founder, is said to have turned to farming in his later years and led a quiet life. The Ryu is still taught today and his headed by the current 13th soke Yamakita Taketada. The Ryu still practices both the Omote and Ura Dachi along with the spells from Mikkyo that were added by Marume Kurando. The Ura Dachi of the school that made it famous is said to be a set of techniques using group tactics while armed with swords.
artical from: http://www.yoshindojo.com/ryuha_files/taisharyu.htm