After having fled from Tosa clan he acted as a royalist, exerting himself into establishing Kameyama-shachu, later Kaientai (a society of master less samurai), a mixture of a trading company and a political organization, mediating collaboration between Satsuma and Choshu, and realizing Taisei-hokan (the Restoration of the Imperial rule).
土佐藩脱藩後、貿易会社と政治組織を兼ねた亀山社中・海援隊(浪士結社)の結成、薩長連合の斡旋、大政奉還の成立に尽力するなど、志士として活動した。