When the Satsuma domain was engaged provocatively in subversive activities (the Incident of setting fire to the residence in Edo of domain of Satsuma, inflicted by the Shonai domain) in the urban area of Edo, the surroundings of Yoshinobu increasingly voiced the desire to defeat the Satsuma domain and accordingly, Yoshinobu attempted to establish a military blockade of Kyoto.
さらに薩摩藩が江戸市街で挑発的な破壊工作を行う（庄内藩の江戸薩摩藩邸焼き討ち事件）と、慶喜の周囲では「討薩」を望む声が高まり、慶喜は軍事的な京の封鎖を試みた。