Okita Soji
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Shieikan
Okita Soji was born as a son of lower Shirakawa han Samurai.He was raised by his oldest sister Mitsu and her husband after father died. When he was around 10, he became pupil of Kondo Shusuke's Shieikan dojo of Tennen Rishin ryu. One of famous episode of this Kenjutsu genius is when he was just 12, he defeated Kenjutsu teacher of Shirakawa han. Soji became head coach of Shieikan when he was only 19.
1863, he joined Roshigumi along with other Shieikan members. ((sources))