Klaaßen Jan is a Shidōin (teacher) of the Hokushin Ittō-ryū Hyōhc in the Chiba-Dōjō. He holds the second scroll, the Hatsu-Mokuroku. In his professional life he works as a risk-management officer of an insurance company.
Since he is six years old he is interested in Japanese martial arts and he started with jūdō. He followed this path for about twenty years actively. With time, he wanted to learn more about the origins of modern jūdō and came in touch with the classical Japanese jūjutsu schools. They are not only focused on unarmed conflict as it is often misunderstood. Most of them have as well weapon training in their curriculum. With this knowledge his interest for those weapons started to grow. Over eleven years ago he got in contact with Sai Tatsushi-Sensei, a Shihan and Menkyo-Kaiden holder of the Bushuden Kiraku-ryū. Soon he became his student and later let the training group in Osnabrück (Germany) as Sai-Sensei moved back to Japan. To this day they maintain a strong friendship.
As Klaaßen-Shidōin moved from Osnabrück to Munich due to career reasons he became aware of the Chiba-Dōjō and joined as a regular student of the Hokushin Ittō-ryū in 2013. He is fascinated by the sophisticated, strong and practical techniques of the school. This fascination grew more and more with the years. In October 2014, at the yearly seminar of the Hokushin Ittō-ryū in Matsushirō, Japan, he was awarded with the Kirigami scroll by Ōtsuka Yōichirō-Sōke.
Back in Munich he intensified his training under Ōtsuka Ryūnosuke-Sensei and deepened his understanding of the techniques greatly. As a result, in January 2016 he was able to pass the second examination and to receive the Hatsu-Mokuroku scroll from Ōtsuka Yōichirō-Sōke.
At the nomination ceremony of the 7th Sōke Ōtsuka Ryūnosuke on March 26th 2016 in Japan he was accorded the honor to perform the Hokushin Ittō-ryū Ai-Kodachi Kata with Lyutov Dmitry-Shidōin.
Currently he supports the training activities at the Chiba-Dōjō and deputizes Ōtsuka Ryūnosuke-Sōke together with the other Shidōin when the latter is teaching in Japan or other branches of the Hokushin Ittō-ryū.