Since a number of the Navy School trainees fought on the Choshu side in Kinmon no hen incident as a reprisal for Ikedaya incident, the Navy School was cracked down on by the Shogunate and KATSU was removed from his position.
池田屋事件への報復である禁門の変で、長州側に多数の海軍塾生が加わっていたため、海軍塾は幕府から弾圧され、勝も解任された。