Kobayashi Sadayuki (小林定之)

11 July 2026

Kobayashi Sadayuki (小林定之; also given as Seijirō 誠次郎) is the figure who bridges the two halves of the transition that Shimoe does not — the battōtai and the sewakari.

An Utsunomiya-domain samurai who received transmission from Chiba Michisaburō (the same Genbukan line as Shimoe), he served in the Keishichō battōtai in the Satsuma Rebellion, then became a gekken sewakari, and afterward opened the Shiseikan (至誠館) dōjō at Kikukawa-chō in Honjo, Tokyo (Hokushin Ittō-ryū (北辰一刀流), n.d.).

Hokushin Ittō-ryū sources count him, with Shimoe, Naitō, and Monna, among the “four heavenly kings” of Chiba Michisaburō’s line (Rekishi to enkaku / jinbutsu-den (歴史と沿革／人物伝), n.d.).

Because he actually fought in the battōtai — which Shimoe did not — he is a clear link from the 1877 corps to the 1879 system.

References

secondary

Hokushin Ittō-ryū (北辰一刀流). n.d. Japanese Wikipedia. Reference article on the school — the composite of Hokushin Musō-ryū and the Nakanishi-ha Ittō-ryū, the licensing structure, the kakari-geiko and shinai-bōgu emphasis, the okugi vocabulary, and the Tōbukan / Meiji succession. Tertiary; corroborates the Chiba article rather than standing independent of it.

Also cited in: Chiba Shūsaku, Naitō Takaharu, Monna Tadashi (門奈正), Shimoe Hidetarō

Rekishi to enkaku / jinbutsu-den (歴史と沿革／人物伝). n.d. Hokushin Ittō-ryū Genbukan (北辰一刀流玄武館). Accessed July 3, 2026. https://hokushin-ittoryu.com/history/. School site; partial to its own lineage, cited for the "four heavenly kings" grouping of Chiba Michisaburō’s line. Corroborate names elsewhere.

Also cited in: Shimoe Hidetarō