Yoshinobu, who is said to have not actively supported starting a war, stayed at Osaka Castle when the defeat of the former Shogunate forces was imminent and he was informed of the issuing of the punitive order against him on February 7; that night Yoshinobu secretly escaped from the castle and retreated to Edo on the Shogunate warship Kaiyo Maru on February 8, which had been anchored at Osaka Bay, along with a few of his close aides as well as Katsukiyo ITAKURA (a senior councilor), Tadato SAKAI (a senior councilor), Katamori MATSUDAIRA (the lord of the Aizu domain) and Sadaki MATSUDAIRA (the lord of the Kuwana domain).
8日、開戦に積極的で無かったとされる慶喜は大坂城におり、旧幕府軍の敗戦が決定的となり、7日には慶喜に対して追討令が出た報を聞くと、その夜僅かな側近及び老中・板倉勝静、同・酒井忠惇、会津藩主・松平容保・桑名藩主・松平定敬と共に密かに城を脱し、大阪湾に停泊中の幕府軍艦・開陽丸で江戸に退却した。