The Choshu clan which was almost conquered concluded a secret alliance with the Satsuma clan (Satsuma-Choshu Alliance) and defeated the army of the bakufu (Japanese feudal government headed by a shogun) at various places on the domain borders.
征伐を受けそうになった長州藩は密かに薩摩藩と秘密同盟を結び（薩長同盟）、幕府軍を藩境の各地で破った。