He participated in Roshigumi with Isami KONDO and others, and became the captain of the second unit when Shinsengumi was formed, playing a central role in Shinsengumi from its early days.
近藤らとともに浪士組に参加し、新撰組結成後は二番隊組長を務めるなど新撰組草創期からの中心人物であった。