Currently translating the timeline on
http://www4.airnet.ne.jp/kotsune/nagakura/shi%20nenpyo.htm
BUT...very interesting stuff I know from it offhand right now:
1. Nagakura met with Shimada Kai in Kyoto in 1890.
2. The Sugimura were the physicians of the Matsumae clan. Nagakura
became the adopted son of the family head Sugimura Matsuhaku in March
1870.
--M.