Having been defeated in the Battle of Toba-Fushimi, Shinsengumi members retreated to Osaka-jo Castle and then took a sea route back to Edo, where Shuhei is said to have run away.
鳥羽・伏見の戦いの敗走の後、新選組は大坂城に撤退して海路江戸へ戻るが、周平は江戸にて脱走したと伝わる。